Operation method and system of liquid-gas dual-mode liquid hydrogen refueling station

Abstract

The invention discloses an operation method and system of a liquid-gas dual-mode liquid hydrogen refueling station, the system realizes the switching of a refueling route through a plurality of liquid hydrogen control valves and a control switch of a gas hydrogen control valve, liquid hydrogen output from a liquid hydrogen storage tank is primarily pressurized through a first liquid hydrogen booster pump, and in the liquid hydrogen refueling route, the liquid hydrogen output from the liquid hydrogen storage tank is pressurized through a second liquid hydrogen booster pump. The liquid hydrogen pressurized for the first time is in a supercooled state and is not easy to evaporate, the generation of BOG is greatly inhibited, the leakage amount of the liquid hydrogen in a liquid-liquid filling process can be reduced, the filling efficiency is improved, in a high-pressure hydrogen filling route, the liquid hydrogen in a supercritical state can also effectively reduce the cavitation problem of a pump during secondary pressurization, waste of liquid hydrogen cold energy is reduced, and the production cost is reduced. High volume efficiency can be effectively guaranteed, and durability of equipment and efficient operation of the hydrogen refueling station are guaranteed.

Description

Technical Field

[0001] This invention relates to the field of hydrogen refueling station technology. More specifically, this invention relates to an operation method and system for a liquid-gas dual-mode liquid hydrogen refueling station. Background Technology

[0002] Hydrogen energy, as a clean and renewable green energy source, boasts advantages such as high energy density and is currently the most promising clean energy source. To promote the widespread use of hydrogen energy, the construction of hydrogen refueling stations is particularly important. As of 2023, China had 422 hydrogen refueling stations, but only one of them (Pinghu, Zhejiang) was a liquid hydrogen refueling station. Compared to high-pressure hydrogen refueling stations, liquid hydrogen refueling stations offer advantages such as higher storage and transportation efficiency, lower construction investment costs, smaller footprint, and lower overall energy consumption, making them a better choice to meet future demands for larger hydrogen refueling needs.

[0003] Unlike typical cryogenic liquids, liquid hydrogen has an extremely low boiling point and is highly volatile during transportation, storage, and pressurization. Therefore, minimizing liquid hydrogen evaporation is the most critical issue in the construction of liquid hydrogen refueling stations. Currently, the two-stage compression pumps widely used in domestic liquid hydrogen refueling stations experience significant liquid hydrogen evaporation and vaporization during compression. This not only increases liquid hydrogen loss but also poses a safety hazard to the pump body due to the overflowing bubbles. One existing solution is to place the entire pump body within a liquid hydrogen pool, utilizing the cold energy of the liquid hydrogen itself to reduce heat leakage during compression. However, this method inevitably limits the size of the liquid hydrogen pump and results in a relatively low output flow rate. For the direct refueling process, due to limitations in the insulation capacity of the refueling pipeline, significant heat leakage and loss occur as the liquid hydrogen passes through the pipeline.

[0004] The 2024 National Key Project Guidelines for Hydrogen Energy Technology of the Ministry of Science and Technology of my country, specifically section 2.1, "Research and Demonstration of Liquid Hydrogen Storage-Supply-Refueling-Utilization Technology for Transportation Hubs," sets an assessment target of "a peak hydrogen refueling flow rate of no less than 15 kg hydrogen / minute for direct liquid hydrogen refueling in vehicles under an outlet pressure of 1.6 MPa." Based on this requirement, reducing the amount of liquid hydrogen evaporated during compression and refueling is particularly important.

[0005] For example, patent application number 202210739681.8 discloses a high-efficiency liquid hydrogen refueling station system and method. Its liquid-gas refueling route uses two liquid hydrogen booster pumps connected in series to gradually compress the liquid hydrogen to 700–900 bar. However, the initial low-pressure booster pump can typically only pressurize the liquid hydrogen to approximately 4–8 bar. Liquid hydrogen, as a cryogenic fluid, has a critical temperature of only 33 K and a critical pressure of approximately 13 bar. Under normal operating conditions, when the pressure of liquid hydrogen is below or close to the critical pressure, its saturated vapor pressure is high, making it highly susceptible to cavitation during subsequent high-pressure compression. Specifically, within the plunger-type compression chamber, due to changes in the flow channel cross-sectional area and transient pressure fluctuations, the local pressure of the liquid hydrogen may momentarily drop below the saturated vapor pressure, thus forming bubbles. These bubbles rapidly collapse in the high-pressure zone, not only causing a loss of effective compressed volume and reducing the pump's volumetric efficiency, but also potentially triggering cavitation and vibration, shortening the equipment's lifespan.

[0006] Currently, most mature 90 MPa liquid hydrogen booster pumps employ a two-stage compression structure: liquid hydrogen is first compressed to 6–8 bar in the first-stage compression chamber, then enters the second-stage compression chamber through the hollow flow channel of the plunger, where it is further compressed to 90 MPa. This approach mitigates the risk of cavitation in the low-pressure section to some extent. However, if a dual-pump series configuration is used, and the first-stage pump only boosts the liquid hydrogen to 8 bar, the liquid hydrogen may still be in a state close to the vaporization boundary during the high-pressure compression process in the second stage. This results in a high risk of cavitation, leading to a decrease in pump volumetric efficiency and insufficient operational stability.

[0007] Therefore, existing technologies still have significant shortcomings in the liquid hydrogen pressurization operation process, with a high risk of cavitation, which seriously affects the operational stability and efficiency of hydrogen refueling stations. Summary of the Invention

[0008] One object of the present invention is to solve at least the above-mentioned problems and to provide at least the advantages that will be described later.

[0009] Another objective of this invention is to provide an operation method and system for a liquid-gas dual-mode liquid hydrogen refueling station, in order to solve the technical problem that the existing hydrogen refueling stations are prone to cavitation risks due to the poor pressurization operation mode of liquid hydrogen.

[0010] To achieve these objectives and other advantages according to the present invention, a method for operating a liquid-gas dual-mode liquid hydrogen refueling station is provided, comprising the following steps: Step S1: Prepare the liquid hydrogen storage system, determine the vehicle's refueling demand type, which is either liquid hydrogen refueling or high-pressure hydrogen refueling, and set the corresponding liquid hydrogen first pressurization target state. Step S2: Switch the liquid hydrogen first pressurization route according to the type of refueling requirement; Step S3: Obtain liquid hydrogen from the liquid hydrogen storage system. If it is liquid hydrogen refueling, execute the liquid-liquid refueling mode. Through the first pressurization, pressurize the liquid hydrogen to a supercooled state, and then refuel it into the vehicle liquid hydrogen cylinder through the liquid hydrogen refueling machine. If high-pressure hydrogen refueling is required, the liquid-gas refueling mode is executed. The liquid hydrogen is pressurized to a supercritical state through the first pressurization, and then the supercritical liquid hydrogen is pressurized a second time. The liquid hydrogen after the second pressurization is heated and vaporized to obtain pressurized hydrogen, which is then stored in stages. Afterwards, the hydrogen of the corresponding pressure level is switched to the on-board hydrogen storage tank through the high-pressure hydrogen refueling machine.

[0011] Preferably, in step S3, when the supercritical hydrogen is pressurized a second time, a second pressurization route and a third pressurization route are set. The rated pressure of the second pressurization route is set to 45 MPa, and the first high-pressure hydrogen is obtained after pressurization. The rated pressure of the third pressurization route is set to 90 MPa, and the second high-pressure hydrogen is obtained after pressurization.

[0012] Preferably, a BOG processing route is also provided, in which the liquid hydrogen storage system is connected to the first BOG processing route. In the first BOG processing route, the BOG from the liquid hydrogen storage system is obtained, compressed, and then fed into the pressurized hydrogen from the second pressurization route for storage.

[0013] Preferably, a BOG processing route is also provided, in which the liquid hydrogen storage system is connected to a second BOG processing route. In the second BOG processing route, the BOG collected from the liquid hydrogen storage system is then connected to the fuel cell power generation system to generate electricity.

[0014] Preferably, in the liquid-liquid refueling mode, after the first pressurization to a subcooled state, the rated pressure of the liquid hydrogen is set to 1.2 MPa. This pressure, under subcooled conditions, is sufficient to suppress phase change in the liquid hydrogen due to heat leakage in the liquid-liquid refueling pipeline. In the liquid-gas refueling mode, after the first pressurization, the rated pressure of the liquid hydrogen is set to 1.6 MPa. Pressurizing the liquid hydrogen to a supercritical state is sufficient to prevent cavitation during the secondary pressurization process in the liquid-gas refueling pipeline.

[0015] Preferably, in the liquid-gas refueling mode, when the rated pressure of the on-board high-pressure hydrogen storage cylinder requiring hydrogen refueling is lower than the rated pressure of the second booster route, the first high-pressure hydrogen is used for refueling; when the rated pressure of the on-board high-pressure hydrogen storage cylinder requiring hydrogen refueling is higher than the rated pressure of the second booster route, the first high-pressure hydrogen is used for pre-charging, and then the second high-pressure hydrogen is used to supplement the pressure to the target required pressure.

[0016] Preferably, it also includes a dynamic scheduling method for hydrogen refueling stations, specifically comprising the following steps: A1. Calculate the capacity of the onboard high-pressure hydrogen storage cylinder and the capacity of the onboard liquid hydrogen cylinder. Set the hydrogen mass range (m1, m2) (kg) for a single high-pressure hydrogen refueling and a single liquid hydrogen refueling. Determine the total liquid hydrogen storage capacity M1 (kg) of the liquid hydrogen storage system. The total mass of the first high-pressure hydrogen in the staged hydrogen storage system is M2 (kg), and the total mass of the second high-pressure hydrogen is M3 (kg). The efficiency of the first liquid hydrogen booster pump in compressing liquid hydrogen to the supercritical state is C. c (kg / min), the efficiency of the first liquid hydrogen booster pump in compressing liquid hydrogen to a subcooled state is C. g (kg / min); A2. When a vehicle enters a hydrogen refueling station, acquire and record the refueling requirements, including the refueling requirement type u and the refueling mass requirement m. i When m n ∈ (m1, m2), allows entry into the corresponding type of annotation area; A3. Based on the allowed time, queue the vehicles and mark the queue number. The current queue sequence is V = {V1, V2, ..., V...} n}, each vehicle V i (u, m) i a i ), where a i For service time, a i =C c / Q or C g / Q, where Q is the injection rate (kg / min); A4. Based on the hydrogen queuing and refueling demand, calculate the total mass of high-pressure hydrogen to be consumed and the total mass of liquid hydrogen to be consumed at the hydrogen refueling station, W. i And update the calculation results and inventory I(t) in real time. Inventory gap ; A5. Calculate the priority of compressing liquid hydrogen to a supercooled or supercritical state, and set the current production urgency score U. U g =α·G g / C g +β·n·a g +γ·S g U c =α·G c / C c +β·n·a c +γ·S c The G / C term represents the urgency of production time. The larger the gap and the lower the compressor capacity, the larger this value, indicating that production needs to start earlier. n is the number of vehicles currently being calculated in the queue. The S term is set as the cost of switching compressor demand. If the compressor is currently producing this type of hydrogen, then S=1 to encourage maintaining it. If switching is required, then S=0 to impose a penalty. α, β, and γ are adjustable weighting coefficients, and α+β+γ=1. A6. Make a decision based on the production urgency score U: If G > 0, the first liquid hydrogen booster pump switches to standby mode to boost liquid hydrogen to a subcooled state. If U g >U c +e opens the second liquid hydrogen control valve and closes the first liquid hydrogen control valve, replenishing the liquid hydrogen to the staged hydrogen storage system after secondary pressurization. Here, e is the hysteresis coefficient, with a value of 0 to 0.25. If U c ≥U g +e, open the first liquid hydrogen control valve, close the second liquid hydrogen control valve, pressurize the liquid hydrogen to a supercooled state, and then refuel the vehicle; If there is no liquid hydrogen refueling queue and the total amount is greater than the consumption, the first liquid hydrogen booster pump enters standby mode.

[0017] Preferably, it also includes a proactive operation planning method based on data prediction, specifically including the following steps: T1. Data Modeling: Based on historical operating data, including at least the changes in hydrogen consumption over time under different refueling modes, the changes in BOG production rate with ambient temperature and tank liquid level, and peak and valley electricity prices, establish a refueling demand prediction model and a BOG production rate prediction model. T2. Generate a plan: Based on the prediction model, actively generate an operation plan for a future time period. The goal of this plan is to minimize the total operating cost of the entire station, which includes electricity costs and liquid hydrogen BOG losses. T3. Planning Execution: The operational plan shall include at least the following: a. BOG processing timing planning: Proactively initiate BOG processing routes before the predicted BOG peak or during periods of low electricity prices. b. High-pressure hydrogen pre-production planning: Before the predicted peak of hydrogen refueling, or during periods of low electricity prices, the first liquid hydrogen booster pump is proactively started to operate in liquid-gas refueling mode to produce high-pressure hydrogen and store it in stages.

[0018] On the other hand, the present invention also provides a liquid-gas dual-mode liquid hydrogen refueling station system, comprising: A liquid hydrogen storage system, comprising multiple liquid hydrogen storage tanks for storing low-pressure liquid hydrogen; The first liquid hydrogen booster pump has its inlet connected to the liquid hydrogen storage tank and is used to boost the liquid hydrogen for the first time to reach a subcooled state or a supercritical state. The liquid-liquid refueling pipeline includes a liquid-liquid line, a first liquid hydrogen control valve, and a liquid hydrogen refueling machine. The first liquid hydrogen control valve is installed at the inlet end of the liquid-liquid line and is connected to the outlet of the first liquid hydrogen booster pump. The outlet of the liquid-liquid line is connected to the inlet of the liquid hydrogen refueling machine. The liquid-gas refueling pipeline includes a liquid-gas split line, a liquid hydrogen booster pump assembly, a vaporizer assembly, a staged hydrogen storage system, and a high-pressure hydrogen dispenser. The inlet of the liquid-gas split line is equipped with a second liquid hydrogen control valve and connected to the outlet of the first liquid hydrogen booster pump. The liquid hydrogen booster pump assembly, used for secondary pressurization of liquid hydrogen, includes a second liquid hydrogen booster pump and a third liquid hydrogen booster pump. The vaporizer assembly includes a first vaporizer and a second vaporizer. The inlet of the second liquid hydrogen booster pump is equipped with a third liquid hydrogen control valve and connected to the outlet of the liquid-gas split line. The outlet of the second liquid hydrogen booster pump is connected to... The inlet of the first vaporizer is connected to and equipped with a fourth liquid hydrogen control valve. The inlet of the third liquid hydrogen booster pump is equipped with a fifth liquid hydrogen control valve and connected to the outlet of the liquid-gas split pipeline. The outlet of the third liquid hydrogen booster pump is connected to the inlet of the second vaporizer and equipped with a sixth liquid hydrogen control valve. The outlet of the first vaporizer is equipped with a first gaseous hydrogen control valve and connected to the staged hydrogen storage system. The outlet of the second vaporizer is equipped with a second gaseous hydrogen control valve and connected to the staged hydrogen storage system. The outlet of the staged hydrogen storage system is equipped with a fifth gaseous hydrogen control valve and connected to the inlet of the high-pressure hydrogen dispenser. The BOG processing system includes a BOG buffer tank and a BOG processing unit. The inlet of the BOG buffer tank is connected to the outlet of the liquid hydrogen storage system and is equipped with a BOG control valve. The outlet of the BOG buffer tank is connected to the inlet of the BOG processing unit. The outlet of the BOG processing unit is equipped with a sixth gaseous hydrogen control valve and is connected to the staged hydrogen storage system.

[0019] Preferably, the staged hydrogen storage system includes a first high-pressure hydrogen storage tank and a second high-pressure hydrogen storage tank. The outlet of the first vaporizer is connected to the inlet of the first high-pressure hydrogen storage tank. The outlet of the first high-pressure hydrogen storage tank is equipped with a third hydrogen control valve and connected to the inlet side of the fifth hydrogen control valve. The outlet of the second vaporizer is connected to the inlet of the second high-pressure hydrogen storage tank. The outlet of the second high-pressure hydrogen storage tank is equipped with a fourth hydrogen control valve and connected to the inlet side of the fifth hydrogen control valve. Safety relief valves, pressure sensors, and / or temperature sensors are also respectively installed at the outlets of the first liquid hydrogen booster pump, the second liquid hydrogen booster pump, and the third liquid hydrogen booster pump.

[0020] The present invention has at least the following beneficial effects: 1) This invention addresses the problem of significant liquid hydrogen evaporation during the pressurization process of traditional external two-stage liquid hydrogen booster pumps by innovatively proposing a supercritical state pressurization method using two pumps in series. Liquid hydrogen is initially pressurized in the first liquid hydrogen booster pump, and the pressurized liquid hydrogen is in a supercritical state. Since there is no gas-liquid interface in the supercritical state, no phase change or bubbles will occur during the subsequent secondary pressurization process, thus completely eliminating the cavitation risk of high-pressure pumps. This effectively ensures high volumetric efficiency and guarantees the durability and efficient operation of the equipment.

[0021] 2) This invention addresses the problem of excessive evaporation of liquid hydrogen in the filling pipeline during the direct liquid-liquid filling process by proposing a method of filling with subcooled liquid hydrogen. The liquid hydrogen is pressurized to a subcooled state in a first liquid hydrogen booster pump. When the subcooled liquid hydrogen passes through the filling pipeline, the heat absorbed will cause it to heat up first instead of directly vaporizing, which greatly suppresses the generation of BOG, reduces liquid hydrogen loss in the pipeline, and improves filling efficiency.

[0022] 3) This invention sets up a scheduling scheme for liquid-liquid hydrogen refueling mode and liquid-gas hydrogen refueling mode, statistically calculates the hydrogen refueling demand of queuing vehicles, takes into account queuing waiting time, compression parameter switching and the compression efficiency weight of booster pump, optimizes the operation time and switching timing of the first liquid hydrogen booster pump, and performs liquid hydrogen refueling or high-pressure hydrogen pre-storage, which significantly improves the operating efficiency of liquid hydrogen booster operation, reduces equipment wear and tear and improves service quality.

[0023] Other advantages, objectives and features of the present invention will become apparent in part from the following description, and in part from those skilled in the art through study and practice of the invention. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the liquid-gas dual-mode liquid hydrogen refueling station of the present invention; Figure 2 A schematic diagram of the structure for setting up a BOG processing route according to an embodiment of the present invention; Figure 3 A schematic diagram illustrating the structure of a BOG processing route according to another embodiment of the present invention; Instruction manual drawing reference numerals: 1. Liquid hydrogen storage tank; 11. BOG control valve; 2. First liquid hydrogen booster pump; 21. First liquid hydrogen control valve; 22. Second liquid hydrogen control valve; 3. Liquid hydrogen booster pump assembly; 31. Second liquid hydrogen booster pump; 32. Third liquid hydrogen booster pump; 4. Vaporizer assembly; 41. First vaporizer; 42. Second vaporizer; 5. Staged hydrogen storage system; 51. First high-pressure hydrogen storage tank; 52. Second high-pressure hydrogen storage tank; 6. Hydrogen refueling unit; 61. Liquid hydrogen refueling machine; 62. High-pressure hydrogen refueling machine; 7. BOG buffer tank; 8. BOG... G processing system; 8a, BOG processing unit; 8b, fuel cell power generation system; 81, sixth gaseous hydrogen control valve; 9, on-board hydrogen storage equipment; 91, on-board high-pressure hydrogen storage cylinder; 92, on-board liquid hydrogen cylinder; 311, third liquid hydrogen control valve; 312, fourth liquid hydrogen control valve; 321, fifth liquid hydrogen control valve; 322, sixth liquid hydrogen control valve; 411, first gaseous hydrogen control valve; 421, second gaseous hydrogen control valve; 511, third gaseous hydrogen control valve; 521, fourth gaseous hydrogen control valve; 621, fifth gaseous hydrogen control valve. Detailed Implementation

[0025] The present invention will now be described in further detail with reference to the accompanying drawings, so that those skilled in the art can implement it based on the description.

[0026] It should be noted that, unless otherwise specified, the experimental methods described in the following embodiments are all conventional methods, and the reagents and materials described are all commercially available unless otherwise specified. In the description of this invention, the terms "lateral", "longitudinal", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0027] like Figure 1-3 As shown, the present invention provides an operation method for a liquid-gas dual-mode liquid hydrogen refueling station, comprising the following steps: Step S1: Prepare the liquid hydrogen storage system, determine the vehicle's refueling demand type, which is either liquid hydrogen refueling or high-pressure hydrogen refueling, and set the corresponding liquid hydrogen first pressurization target state. Step S2: Switch the liquid hydrogen first pressurization route according to the type of refueling requirement; Step S3: Obtain liquid hydrogen from the liquid hydrogen storage system. If it is liquid hydrogen refueling, execute the liquid-liquid refueling mode. Through the first pressurization, pressurize the liquid hydrogen to a supercooled state, and then refuel it into the vehicle liquid hydrogen cylinder 92 through the liquid hydrogen refueling machine 61. If high-pressure hydrogen refueling is required, the liquid-gas refueling mode is executed. The liquid hydrogen is pressurized to a supercritical state through the first pressurization, and then the supercritical liquid hydrogen is pressurized a second time. The liquid hydrogen after the second pressurization is heated and vaporized to obtain pressurized hydrogen, which is then stored in stages. Afterwards, the high-pressure hydrogen refueling machine 62 switches to refuel the hydrogen of the corresponding pressure level into the on-board hydrogen storage cylinder.

[0028] The operation method of the liquid-gas dual-mode liquid hydrogen refueling station of the present invention utilizes the same first liquid hydrogen booster pump 2 for initial pressurization. Different liquid hydrogen initial pressurization parameters are set for the liquid-liquid refueling mode and the liquid-gas refueling mode, and corresponding refueling routes are set. In the liquid hydrogen refueling route, the liquid hydrogen after the first pressurization is in a supercooled state and is not easy to evaporate, which greatly suppresses the generation of BOG and reduces the leakage of liquid hydrogen during the liquid-liquid refueling process, thereby improving the refueling efficiency. In the high-pressure hydrogen refueling route, the supercritical liquid hydrogen can also effectively reduce the pump cavitation problem during the second pressurization, reduce the waste of liquid hydrogen cold energy, effectively ensure high volumetric efficiency, and ensure the durability and efficient operation of the equipment.

[0029] The specific operation method of the liquid-gas dual-mode liquid hydrogen refueling station is as follows: In step S3, when the supercritical hydrogen is pressurized for the second time, a second pressurization route and a third pressurization route are set. The rated pressure of the second pressurization route is set to 45 MPa, and the first high-pressure hydrogen is obtained after pressurization. The rated pressure of the third pressurization route is set to 90 MPa, and the second high-pressure hydrogen is obtained after pressurization.

[0030] Preferably, two BOG processing routes are also provided. The first BOG processing route is where the liquid hydrogen storage system is connected to the first BOG processing route. In the first BOG processing route, the BOG from the liquid hydrogen storage system is obtained, compressed, and then fed into the pressurized hydrogen from the second pressurization route for storage.

[0031] Second BOG processing route: The liquid hydrogen storage system is connected to the second BOG processing route. In the second BOG processing route, the BOG collected from the liquid hydrogen storage system is connected to the fuel cell power generation system 8b to generate electricity.

[0032] Preferably, in the liquid-liquid refueling mode, the rated pressure of liquid hydrogen after the first pressurization is set to 1.2 MPa, and in the liquid-gas refueling mode, the rated pressure of liquid hydrogen after the first pressurization is set to 1.6 MPa.

[0033] Furthermore, in the liquid-gas refueling mode, when the rated pressure of the on-board high-pressure hydrogen storage cylinder 91 that requires hydrogen refueling is lower than the rated pressure of the second booster route, the first high-pressure hydrogen is used for refueling; when the rated pressure of the on-board high-pressure hydrogen storage cylinder 91 that requires hydrogen refueling is higher than the rated pressure of the second booster route, the first high-pressure hydrogen is used for pre-charging, and then the second high-pressure hydrogen is used to supplement the pressure to the target required pressure.

[0034] In another preferred technical solution, a dynamic scheduling method for hydrogen refueling stations is also included, specifically comprising the following steps: A1. Calculate the capacity of the on-board high-pressure hydrogen storage cylinder 91 and the capacity of the on-board liquid hydrogen cylinder 92. Set the hydrogen mass range (m1, m2) (kg) for a single high-pressure hydrogen refueling and a single liquid hydrogen refueling. Determine the total liquid hydrogen storage capacity M1 (kg) of the liquid hydrogen storage system. The total mass of the first high-pressure hydrogen in the staged hydrogen storage system 5 is M2 (kg), the total mass of the second high-pressure hydrogen is M3 (kg), and the efficiency of the first liquid hydrogen booster pump 2 in compressing liquid hydrogen to the supercritical state is C. c (kg / min), the efficiency of the first liquid hydrogen booster pump 2 in compressing liquid hydrogen to a subcooled state is C. g (kg / min); The hydrogen refueling mass range for general vehicles can be set according to the capacity of the existing common vehicle-mounted high-pressure hydrogen storage cylinder 91 and vehicle-mounted liquid hydrogen cylinder 92 to avoid exceeding the refueling capacity of the hydrogen refueling station or causing abnormalities.

[0035] A2. Configure a refueling reporting module, a gate module, and an early warning module. When a vehicle enters a hydrogen refueling station, it should input its refueling requirements, including the refueling requirement type (u) and the required refueling quality (m). i When m n If the hydrogen refueling station is not within the service capacity of the current hydrogen refueling station (m1, m2), entry into the corresponding refueling area is permitted; otherwise, entry into the refueling area is temporarily not permitted.

[0036] A3. Based on the allowed time, queue the vehicles and mark the queue numbers from 1 to n. The current queue sequence is V = {V1, V2, ..., V...} n}, each vehicle V i (u, m) i a i ), where a i For service time, a i =C c / Q or C g / Q, where Q is the refueling rate (kg / min); the service time can be set by the user and includes the hydrogen preparation time and hydrogen refueling time for a single vehicle, as well as the time the vehicle spends in front of the hydrogen refueling machine.

[0037] A4. Based on the hydrogen queuing and refueling demand, calculate the total mass of high-pressure hydrogen to be consumed and the total mass of liquid hydrogen to be consumed at the hydrogen refueling station, W. i And update the calculation results and inventory I(t) in real time. Inventory gap The maximum value of the inventory is equal to the total hydrogen storage M in step A1.

[0038] A5. Calculate the priority of compressing liquid hydrogen to a supercooled or supercritical state, and set the current production urgency score U. Due to the liquid-liquid refueling mode, refueling is performed after pressurization by the first liquid hydrogen booster pump 2. Unlike high-pressure hydrogen, a staged hydrogen storage system 5 is set up with a reserve storage capacity of 0. The hydrogen preparation time for liquid-liquid refueling is longer than that for liquid hydrogen, i.e., a g Greater than a c , U g =α·G g / C g +β·n·a g +γ·S g U c =α·G c / C c +β·n·a c +γ·S c The G / C term represents the urgency of production time. The larger the gap and the lower the compressor capacity, the larger this value, indicating that production needs to start earlier. n is the number of vehicles currently in the queue. The S term sets the cost of switching compressor demand. If the compressor is currently producing this type of hydrogen, S=1 to encourage maintaining the status quo; if switching is required, S=0 to impose a penalty. α, β, and γ are adjustable weighting coefficients, where α+β+γ=1. The values ​​can be calculated as follows: β = β0 + Δβ, Δβ = 0.2 × (0.5 × L + 0.3 × W + 0.2 × E), L is the queue length factor, L = min(1, current number of vehicles in the queue / maximum tolerable queue length), W is the waiting time factor, W = min(1, current longest waiting time / maximum tolerable waiting time), T is the type imbalance factor, T = |number of gaseous hydrogen vehicles - number of liquid hydrogen vehicles| / total number of vehicles, E is the urgency factor, E = number of vehicles with emergency demand flags / total number of vehicles, α0 = 0.2, β0 = 0.7, γ0 = 0.1, γ = γ0 × (1 - 0.5 × L - 0.3 × W - 0.2 × T), α = 1 - β - γ, and then normalization is performed.

[0039] A6. Make a decision based on the production urgency score U: If G > 0, the first liquid hydrogen booster pump 2 switches to standby mode to boost liquid hydrogen to a subcooled state. If U g >U c+e opens the second liquid hydrogen control valve 22 and closes the first liquid hydrogen control valve 21, replenishing the liquid hydrogen to the staged hydrogen storage system 5 after secondary pressurization. Here, e is the hysteresis coefficient, ranging from 0 to 0.25, which can be determined by the number of vehicles in the queue. For example, if the number of vehicles in the queue on the current refueling line is less than or equal to 2, e is 0.2-0.25; if the number of vehicles in the queue is 2-8, e is 0.1-0.15; and if the number of vehicles in the queue is greater than 8, e is 0.03-0.05.

[0040] If U c ≥U g +e, open the first liquid hydrogen control valve 21, close the second liquid hydrogen control valve 22, pressurize the liquid hydrogen to a supercooled state, and then refuel the vehicle with liquid hydrogen; If there is no liquid hydrogen refueling queue and the total amount is greater than the consumption, the first liquid hydrogen booster pump 2 enters standby mode.

[0041] By setting up a dynamic scheduling method for hydrogen refueling stations, based on the stored liquid hydrogen to be compressed and the mass of compressed and stored high-pressure hydrogen, adjustments are made dynamically according to the refueling needs of vehicles at the stations. This ensures that vehicle waiting times are short. If there is sufficient storage of high-pressure hydrogen, high-pressure hydrogen refueling machine 62 can be directly arranged to refuel vehicles. Vehicles requiring liquid hydrogen refueling can be directly arranged at liquid hydrogen refueling machine 61, operating in liquid-liquid refueling mode. When the storage of high-pressure hydrogen is insufficient, an immediate scheduling scheme needs to be activated to ensure relatively short vehicle waiting times and fewer compressor operation switching times. This improves the operating efficiency of hydrogen refueling station equipment, reduces equipment wear and tear, enhances the safety of hydrogen refueling operations, reduces BOG generation, and provides early warning when the refueling capacity is exceeded.

[0042] Another technical solution also includes a proactive operation planning method based on data prediction, which specifically includes the following steps: T1. Data Modeling: Based on historical operating data, including at least the changes in hydrogen consumption over time under different refueling modes, the changes in BOG production rate with ambient temperature and tank liquid level, and peak and valley electricity prices, establish a refueling demand prediction model and a BOG production rate prediction model. T2. Generate a plan: Based on the prediction model, actively generate an operation plan for a future time period. The goal of this plan is to minimize the total operating cost of the entire station, which includes electricity costs and liquid hydrogen BOG losses. T3. Planning Execution: The operational plan shall include at least the following: a. BOG processing timing planning: Proactively initiate BOG processing routes before the predicted BOG peak or during periods of low electricity prices. b. High-pressure hydrogen pre-production planning: Before the predicted peak of hydrogen refueling, or during periods of low electricity prices, the first liquid hydrogen booster pump is proactively started to operate in liquid-gas refueling mode to produce high-pressure hydrogen and store it in stages.

[0043] Research the operational needs of hydrogen refueling stations over time, prepare or switch in advance to prepare high-pressure compressed hydrogen or compression parameters, optimize the operating efficiency of hydrogen refueling stations, and for periods with low hydrogen demand, do not rush to use compressors to process compressed hydrogen, and manage energy accordingly.

[0044] Correspondingly, the present invention also provides a liquid-gas dual-mode liquid hydrogen refueling station system, combined with Figure 1-3 As shown, it includes: A liquid hydrogen storage system, comprising multiple liquid hydrogen storage tanks 1 for storing low-pressure liquid hydrogen; The first liquid hydrogen booster pump 2 has its inlet connected to the liquid hydrogen storage tank 1 and is used to boost the liquid hydrogen for the first time to reach a subcooled state or a supercritical state. The liquid-liquid filling pipeline includes a liquid-liquid line, a first liquid hydrogen control valve 21, and a liquid hydrogen refueling machine 61. The first liquid hydrogen control valve 21 is installed at the inlet end of the liquid-liquid line and is connected to the outlet of the first liquid hydrogen booster pump 2. The outlet of the liquid-liquid line is connected to the inlet of the liquid hydrogen refueling machine 61. The liquid-gas refueling pipeline includes a liquid-gas split line, a liquid hydrogen booster pump group 3, a vaporizer group 4, a staged hydrogen storage system 5, and a high-pressure hydrogen dispenser 62. The inlet of the liquid-gas split line is equipped with a second liquid hydrogen control valve 22 and connected to the outlet of the first liquid hydrogen booster pump 2. The liquid hydrogen booster pump group 3 is used for secondary pressurization of liquid hydrogen and includes a second liquid hydrogen booster pump 31 and a third liquid hydrogen booster pump 32. The vaporizer group 4 includes a first vaporizer 41 and a second vaporizer 42. The inlet of the second liquid hydrogen booster pump 31 is equipped with a third liquid hydrogen control valve 311 and connected to the outlet of the liquid-gas split line. The outlet of the second liquid hydrogen booster pump 31 is connected to the first vaporizer... The inlet of the first vaporizer 41 is connected to and equipped with a fourth liquid hydrogen control valve 312. The inlet of the third liquid hydrogen booster pump 32 is equipped with a fifth liquid hydrogen control valve 321 and connected to the outlet of the liquid-gas split pipeline. The outlet of the third liquid hydrogen booster pump 32 is connected to the inlet of the second vaporizer 42 and equipped with a sixth liquid hydrogen control valve 322. The outlet of the first vaporizer 41 is equipped with a first gas hydrogen control valve 411 and connected to the staged hydrogen storage system 5. The outlet of the second vaporizer 42 is equipped with a second gas hydrogen control valve 421 and connected to the staged hydrogen storage system 5. The outlet of the staged hydrogen storage system 5 is equipped with a fifth gas hydrogen control valve 621 and connected to the inlet of the high-pressure hydrogen dispenser 62. The BOG processing system 8 includes a BOG buffer tank 7 and a BOG processing unit 8a. The inlet of the BOG buffer tank 7 is connected to the outlet of the liquid hydrogen storage system and is equipped with a BOG control valve 11. The outlet of the BOG buffer tank 7 is connected to the inlet of the BOG processing unit 8a. The outlet of the BOG processing unit 8a is equipped with a sixth gaseous hydrogen control valve 81 and is connected to the staged hydrogen storage system 5.

[0045] Specifically, the staged hydrogen storage system 5 includes a first high-pressure hydrogen storage tank 51 and a second high-pressure hydrogen storage tank 52. The outlet of the first vaporizer 41 is connected to the inlet of the first high-pressure hydrogen storage tank 51. The outlet of the first high-pressure hydrogen storage tank 51 is equipped with a third hydrogen control valve 511 and is connected to the inlet side of the fifth hydrogen control valve 621. The outlet of the second vaporizer 42 is connected to the inlet of the second high-pressure hydrogen storage tank 52. The outlet of the second high-pressure hydrogen storage tank 52 is equipped with a fourth hydrogen control valve 521 and is connected to the inlet side of the fifth hydrogen control valve 621. Safety relief valves, pressure sensors, and / or temperature sensors are also respectively installed at the outlets of the first liquid hydrogen booster pump 2, the second liquid hydrogen booster pump 31, and the third liquid hydrogen booster pump 32. The flow direction of liquid hydrogen after the first stage of pressurization is regulated by setting a first liquid hydrogen control valve 21, a second liquid hydrogen control valve 22, a third liquid hydrogen control valve 311, a fourth liquid hydrogen control valve 312, a fifth liquid hydrogen control valve 321, and a sixth liquid hydrogen control valve 322.

[0046] The liquid-gas dual-mode liquid hydrogen refueling station system of the present invention provides liquid hydrogen from liquid hydrogen storage tank 1, which is initially pressurized to a supercritical state by a first liquid hydrogen booster pump 2, and then further pressurized by a high-pressure liquid hydrogen booster pump. After being vaporized by a vaporizer, it is then refueled, realizing the liquid-gas refueling mode. Alternatively, it can be compressed to a subcooled state by the first liquid hydrogen booster pump 2 and then directly refueled, realizing the liquid-liquid refueling mode. The refueling route can be switched by the control switches of multiple liquid hydrogen control valves and gas hydrogen control valves, which improves the control capability and operating efficiency of the hydrogen refueling station system.

[0047] The following provides specific implementation methods for a liquid-gas dual-mode liquid hydrogen refueling station system under different modes: Example 1: When the hydrogen being added is high-pressure hydrogen storage, a liquid-to-gas filling pipeline is used. At the start of filling, the second liquid hydrogen control valve 22 on the liquid-to-gas filling pipeline is opened, and the first liquid hydrogen control valve 21 on the liquid-to-liquid filling pipeline is closed. Liquid hydrogen flows out from the liquid hydrogen storage tank 1 and is pressurized by the first liquid hydrogen booster pump 2. The rated pressure of the liquid hydrogen after the first pressurization is set to 1.6 MPa, at which point the liquid hydrogen is in a supercritical state.

[0048] Subsequently, the liquid hydrogen is pressurized by either the second liquid hydrogen booster pump 31 or the third liquid hydrogen booster pump 32. The liquid hydrogen entering the second liquid hydrogen booster pump 31 is compressed to 45 MPa, and the liquid hydrogen entering the third liquid hydrogen booster pump 32 is compressed to 90 MPa. After compression by the second liquid hydrogen booster pump 31, the liquid hydrogen is vaporized by the corresponding downstream first vaporizer 41 and then connected to the first high-pressure hydrogen storage tank 51. After compression by the third liquid hydrogen booster pump 32, the liquid hydrogen is vaporized by the corresponding downstream second vaporizer 42 and then connected to the second high-pressure hydrogen storage tank 52.

[0049] When the rated pressure of the on-board high-pressure hydrogen storage cylinder 91 requiring hydrogen refueling is 35 MPa, refueling is performed by the first high-pressure hydrogen storage tank 51; when the rated pressure of the on-board high-pressure hydrogen storage cylinder 91 requiring hydrogen refueling is 70 MPa, pre-filling is performed by the first high-pressure hydrogen storage tank 51, and subsequently replenished to the target pressure by the second high-pressure hydrogen storage tank 52. This embodiment utilizes stored high-pressure hydrogen for rapid refueling to the vehicle's required rated pressure.

[0050] Example 2: When the hydrogen being added is high-pressure hydrogen storage, a liquid-to-gas filling pipeline is used. At the start of filling, the second liquid hydrogen control valve 22 on the liquid-to-gas filling pipeline is opened, and the first liquid hydrogen control valve 21 on the liquid-to-liquid filling pipeline is closed. Liquid hydrogen flows out from the liquid hydrogen storage tank 1 and is pressurized by the first liquid hydrogen booster pump 2. The rated pressure of the pressurized liquid hydrogen is set to 1.6 MPa, at which point the liquid hydrogen is in a supercritical state.

[0051] When the rated pressure of the on-board high-pressure hydrogen storage cylinder 91 requiring hydrogen refueling is 35 MPa, the supercritical hydrogen, after being compressed by the first liquid hydrogen booster pump 2, is further compressed to 45 MPa by the second liquid hydrogen booster pump 31, and then vaporized by the connected first vaporizer 41. After being buffered by the first high-pressure hydrogen storage tank 51, it is directly added to the on-board high-pressure hydrogen storage cylinder 91. When the rated pressure of the on-board high-pressure hydrogen storage cylinder 91 requiring hydrogen refueling is 70 MPa, the supercritical hydrogen, compressed by the first liquid hydrogen booster pump 2, is further compressed to 45 MPa by the second liquid hydrogen booster pump 31. It is then vaporized by the connected first vaporizer 41, buffered by the first high-pressure hydrogen storage tank 51, and added to the on-board high-pressure hydrogen storage cylinder 91. When the pressure reaches a certain value, the system switches to the third liquid hydrogen booster pump 32 to compress it to 90 MPa. After vaporization by the second vaporizer 42, it continues to be refueled to the target pressure after passing through the buffer tank. This embodiment achieves dynamic operation and refueling of the hydrogen refueling station under the required rated pressure for the vehicle.

[0052] Example 3: When the hydrogen being refueled is liquid hydrogen storage, a liquid-to-liquid refueling pipeline is used. At the start of refueling, the first liquid hydrogen control valve 21 on the liquid-to-liquid refueling pipeline is opened, and the second liquid hydrogen control valve 22 on the liquid-to-gas refueling pipeline is closed. Liquid hydrogen flows out from the liquid hydrogen storage tank 1 and is pressurized by the first liquid hydrogen booster pump 2. The rated pressure of the pressurized liquid hydrogen is set to 1.2 MPa, at which point the liquid hydrogen is in a subcooled state. The pressurized liquid hydrogen is then filled into the on-board liquid hydrogen cylinder 92 via the subcooled liquid hydrogen refueling machine 61. This embodiment achieves dynamic refueling operation of the hydrogen refueling station at the rated pressure required by the vehicle.

[0053] Example 4: This embodiment includes a BOG processing system 8 to improve the overall hydrogen energy utilization efficiency of the hydrogen refueling station. Two preferred schemes are described below. Figure 2 and Figure 3 As shown.

[0054] like Figure 2 As shown, when the BOG processing system 8 is a compression and reuse scheme, the BOG from the liquid hydrogen storage tank 1 is compressed by the BOG processing unit 8a after passing through the BOG buffer tank 7, and then replenished to the first high-pressure hydrogen storage tank 51 with a pressure of 45 MPa for subsequent refueling.

[0055] like Figure 3 As shown, when the BOG processing system 8 is a cogeneration scheme, a fuel cell power generation system 8b is used to generate electricity from the collected BOG for use within the station.

[0056] Example 5: This embodiment provides a data-driven proactive operation planning method, which aims to achieve the lowest overall operating cost while ensuring refueling services.

[0057] T1. Data Modeling: The control system collects and learns from historical data, including but not limited to the following example models: Demand Model: The system found that the peak time for 70 MPa high-pressure hydrogen refueling is from 7 to 9 a.m. every day; while the demand for liquid hydrogen refueling is stable in the afternoon.

[0058] BOG model: The system found that the BOG generation rate is fastest between 1 pm and 4 pm every day when the ambient temperature is the highest and the liquid hydrogen storage tank level is below 30%.

[0059] Energy Model: The system accesses grid data and learns that electricity prices are at their lowest between 1 a.m. and 5 a.m. every day.

[0060] T2. Generating and executing plans, for example: At 0:00 AM on a certain day, the system control center generates the following proactive operation plan based on the above model: Planning objectives: Increase the inventory of 90 MPa high-pressure hydrogen storage tanks to 90% before the 7:00 AM peak period; and reduce the pressure of the BOG buffer tanks to a safe low of 20% before the 1:00 PM BOG peak period.

[0061] Planning activities (1 AM - 5 AM, during off-peak electricity prices): Start the first liquid hydrogen booster pump P1 to produce gas: The system actively starts the first liquid hydrogen booster pump and switches to liquid-gas filling mode. The liquid hydrogen is boosted to the supercritical state by the first liquid hydrogen booster pump, and then passed through the third liquid hydrogen booster pump and the second gasifier to fill the 90MPa high-pressure hydrogen storage tank for high-pressure hydrogen pre-production.

[0062] BOG compression is initiated: At the same time, the system also actively starts the BOG processing unit to compress the BOG collected in the BOG buffer tank and replenish it to the 45 MPa medium-pressure hydrogen storage tank.

[0063] Planning results: Both the P1 and BOG processing units, which are high-energy-consuming components, operate during off-peak electricity prices, saving on electricity costs.

[0064] T3, Execution Plan: Following the execution plan of T2, at 7:00 AM, customers can quickly refuel directly from the storage tank without waiting for on-site gas generation at P1, improving service efficiency. At 1:00 PM, the BOG buffer tank is at a low pressure state, with sufficient capacity to cope with the peak BOG generation, preventing hydrogen from being released due to overpressure and reducing hydrogen loss.

[0065] Integration with dynamic scheduling: During the execution of the above "active planning" process, if a vehicle suddenly enters the station, the system will use the dynamic scheduling method for hydrogen refueling stations of this invention to perform allocation calculations. The system will calculate the U score and determine whether "serving the vehicle that cuts in line" or "continuing to execute the plan" has a higher priority.

[0066] Although embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. For those skilled in the art, other modifications can be easily made. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. A method of operating a liquid-gas dual mode liquid hydrogen refueling station, characterized in that, The method comprises the following steps: Step S1, preparing a liquid hydrogen storage system, judging the filling demand type of the vehicle, and setting a liquid hydrogen first pressurization target state corresponding to liquid hydrogen filling or high-pressure hydrogen gas filling; Step S2, switching the liquid hydrogen first pressurization route according to the filling demand type; Step S3, obtaining liquid hydrogen from the liquid hydrogen storage system, if it is liquid hydrogen filling, executing a liquid-liquid filling mode, pressurizing the liquid hydrogen to a supercooled state through first pressurization, and then filling the liquid hydrogen into a vehicle-mounted liquid hydrogen bottle through a liquid hydrogen filling machine; if it is high-pressure hydrogen gas filling, executing a liquid-gas filling mode, pressurizing the liquid hydrogen to a supercritical state through first pressurization, then second pressurizing the liquid hydrogen in the supercritical state, heating and vaporizing the second-pressurized liquid hydrogen to obtain pressurized hydrogen gas and store it in stages, and then switching the hydrogen gas of the corresponding pressure level to the vehicle-mounted hydrogen storage bottle through a high-pressure hydrogen gas filling machine.

2. The method of operating a liquid-gas dual mode liquid hydrogen filling station of claim 1, characterized in that, In step S3, when the supercritical state hydrogen is second-pressurized, a second pressurization route and a third pressurization route are set, the rated pressure of the second pressurization route is set to 45 MPa, and the first high-pressure hydrogen gas is obtained after pressurization, and the rated pressure of the third pressurization route is set to 90 MPa, and the second high-pressure hydrogen gas is obtained after pressurization.

3. The method of operating a liquid-gas dual mode liquid hydrogen filling station of claim 2, characterized in that, A BOG processing route is also provided, and the liquid hydrogen storage system is connected to the first BOG processing route, in which the BOG of the liquid hydrogen storage system is compressed and then stored in the pressurized hydrogen gas of the second pressurization route.

4. The method of operating a liquid-gas dual mode liquid hydrogen filling station of claim 2, wherein, A BOG processing route is also provided, and the liquid hydrogen storage system is connected to the second BOG processing route, in which the BOG of the liquid hydrogen storage system is collected and then connected to a fuel cell power generation system for power generation.

5. The method of operating a liquid-gas dual mode liquid hydrogen filling station of claim 1, wherein, In the liquid-liquid filling mode, the liquid hydrogen is pressurized to a supercooled state through first pressurization, and the pressure in the supercooled state is sufficient to inhibit the phase change of the liquid hydrogen in the liquid-liquid filling pipeline due to heat leakage; in the liquid-gas filling mode, the liquid hydrogen is pressurized to a supercritical state through first pressurization, and the supercritical state is sufficient to avoid cavitation of the liquid hydrogen during the second pressurization process in the liquid-gas filling pipeline.

6. The method of operating a liquid-gas dual mode liquid hydrogen filling station of claim 1, wherein, In the liquid-gas filling mode, when the rated pressure of the vehicle-mounted high-pressure hydrogen storage bottle that needs to be filled with hydrogen gas is lower than the rated pressure of the second pressurization route, the first high-pressure hydrogen gas is used for filling; when the rated pressure of the vehicle-mounted high-pressure hydrogen storage bottle that needs to be filled with hydrogen gas is higher than the rated pressure of the second pressurization route, the first high-pressure hydrogen gas is pre-charged, and the second high-pressure hydrogen gas is supplemented to the target required pressure.

7. The method of operating a liquid-gas dual mode liquid hydrogen filling station of claim 1, wherein, The method also includes a dynamic scheduling method for hydrogen filling stations, which specifically comprises the following steps: A1, the capacity of the vehicle-mounted high-pressure hydrogen storage bottle, the capacity of the vehicle-mounted liquid hydrogen bottle, set the hydrogen mass range (m1, m2) (kg) of single high-pressure hydrogen refueling and single liquid hydrogen refueling, determine the total liquid hydrogen storage amount M1 (kg) of the liquid hydrogen storage system, the total mass of the first high-pressure hydrogen of the hierarchical hydrogen storage system is M2 (kg), the total mass of the second high-pressure hydrogen is M3 (kg), the efficiency of the first liquid hydrogen booster pump for compressing liquid hydrogen to supercritical state is C c (kg / min), the efficiency of the first liquid hydrogen booster pump for compressing liquid hydrogen to supercritical state is C g (kg / min); A2, when the vehicle enters the hydrogen refueling station, the refueling demand is obtained and recorded, including the refueling demand type u and the refueling quality demand m i When m n ∈ (m1, m2), the entry into the refueling area of the corresponding type is allowed; A3, according to the allowable time, the vehicle queue, marking the queue number, the current queue vehicle sequence V = {V1, V2, …, Vn}, each vehicle V n (u, m i , a i , a i ), wherein a i is the service time, a i =C c / Q or C g / Q, Q is the filling rate (kg / min); A4、According to the hydrogen refueling demand, calculate the total mass of hydrogen gas to be consumed, the total mass of liquid hydrogen to be consumed W i , and update the calculation results and inventory I(t) in real time, , inventory gap ; A5, calculating the priority of pressurizing the liquid hydrogen to a supercooled state or a supercritical state, setting a current production urgency score U, U g = α · G g / C g + β · n · a g + γ · S g U c = α · G c / C c + β · n · a c + γ · S c G / C items represent the production time urgency, the larger the gap and the lower the compressor capacity, the larger the value, which means that production needs to start earlier, n is the current calculation of the number of queued vehicles, S item is set as the compression demand switching cost, if the current compressor is in the state of producing this type of hydrogen, S=1, encouraging to maintain, if switching is needed, S=0, imposing a penalty, and a, b, and g are adjustable weight coefficients, a+b+g=1; A6、According to the production urgency score U, make a decision: If G>0, the first liquid hydrogen booster pump switches to standby for setting the liquid hydrogen booster to the supercooled state; If U g >U c +e, open the second liquid hydrogen control valve and close the first liquid hydrogen control valve to supplement the storage of the liquid hydrogen in the hierarchical hydrogen storage system after the secondary pressurization of the liquid hydrogen, wherein e is a hysteresis coefficient, and the value is 0-0.

25. If U c ≥ U g + e, open the first liquid hydrogen control valve and close the second liquid hydrogen control valve to pressurize the liquid hydrogen to a supercooled state and then fill the vehicle; If there is no liquid hydrogen filling queue and the total amount is greater than the consumption amount, the first liquid hydrogen booster pump enters the standby state.

8. The method of operating a liquid-gas dual mode liquid hydrogen filling station of claim 1, wherein, It also includes an active operation planning method based on data prediction, which specifically includes the following steps: T1, data modeling: based on historical operation data, the operation data at least includes the change of hydrogen consumption with time under different filling modes, the change of BOG generation rate with ambient temperature and storage tank liquid level, and the peak and valley electricity price of the power grid, a filling demand prediction model and a BOG generation rate prediction model are established; T2, generate planning: based on the prediction model, automatically generate an operation planning for a future time period, the goal of the planning is to minimize the total operation cost of the whole station, and the total operation cost includes electricity cost and liquid hydrogen BOG loss; T3, planning execution: the operation planning at least includes: a. BOG processing timing planning, actively start the BOG processing route before the predicted BOG generation peak, or during the electricity price low valley period; b. High-pressure hydrogen pre-preparation planning, actively start the first liquid hydrogen booster pump to run the liquid-gas filling mode before the predicted hydrogen filling peak, or during the electricity price low valley period, prepare high-pressure hydrogen and store it in stages.

9. A liquid-gas dual mode liquid hydrogen refueling station system, characterized by, It includes: A liquid hydrogen storage system, which includes a plurality of liquid hydrogen storage tanks for storing low-pressure liquid hydrogen; A first liquid hydrogen booster pump, the inlet of which is in communication with the liquid hydrogen storage tank, for first boosting the liquid hydrogen to a supercooled state or a supercritical state; A liquid-liquid filling pipeline, which includes a liquid-liquid pipeline, a first liquid hydrogen control valve, and a liquid hydrogen filling machine, the first liquid hydrogen control valve is arranged at the inlet end of the liquid-liquid pipeline and connected with the outlet of the first liquid hydrogen booster pump, and the outlet of the liquid-liquid pipeline is connected with the inlet of the liquid hydrogen filling machine; A liquid-gas filling pipeline, which includes a liquid-gas diversion pipeline, a liquid hydrogen booster pump group, a gasifier group, a hierarchical hydrogen storage system, and a high-pressure hydrogen filling machine, the inlet end of the liquid-gas diversion pipeline is provided with a second liquid hydrogen control valve and connected with the outlet of the first liquid hydrogen booster pump, the liquid hydrogen booster pump group is used for second boosting of the liquid hydrogen and includes a second liquid hydrogen booster pump and a third liquid hydrogen booster pump, the gasifier group includes a first gasifier and a second gasifier, the inlet of the second liquid hydrogen booster pump is provided with a third liquid hydrogen control valve and connected with the outlet of the liquid-gas diversion pipeline, the outlet of the second liquid hydrogen booster pump is connected with the inlet of the first gasifier and provided with a fourth liquid hydrogen control valve, the inlet of the third liquid hydrogen booster pump is provided with a fifth liquid hydrogen control valve and connected with the outlet of the liquid-gas diversion pipeline, the outlet of the third liquid hydrogen booster pump is connected with the inlet of the second gasifier and provided with a sixth liquid hydrogen control valve, the outlet of the first gasifier is provided with a first gas hydrogen control valve and connected with the hierarchical hydrogen storage system, the outlet of the second gasifier is provided with a second gas hydrogen control valve and connected with the hierarchical hydrogen storage system, and the outlet of the hierarchical hydrogen storage system is provided with a fifth gas hydrogen control valve and connected with the inlet of the high-pressure hydrogen filling machine. The BOG processing system comprises a BOG buffer tank, a BOG processing unit, an inlet of the BOG buffer tank is connected with an outlet of the liquid hydrogen storage system and is provided with a BOG control valve, an outlet of the BOG buffer tank is connected with an inlet of the BOG processing unit, and an outlet of the BOG processing unit is provided with a sixth hydrogen control valve and is connected with the hierarchical hydrogen storage system.

10. The liquid-gas dual mode liquid hydrogen filling station system of claim 9, wherein, The hierarchical hydrogen storage system comprises a first high-pressure hydrogen storage tank and a second high-pressure hydrogen storage tank, an outlet of the first gasifier is connected with an inlet of the first high-pressure hydrogen storage tank, an outlet of the first high-pressure hydrogen storage tank is provided with a third hydrogen control valve and is connected with an inlet side of the fifth hydrogen control valve, an outlet of the second gasifier is connected with an inlet of the second high-pressure hydrogen storage tank, an outlet of the second high-pressure hydrogen storage tank is provided with a fourth hydrogen control valve and is connected with the inlet side of the fifth hydrogen control valve, and a safety relief valve, a pressure sensor and / or a temperature sensor are further respectively arranged at outlets of the first liquid hydrogen booster pump, the second liquid hydrogen booster pump and the third liquid hydrogen booster pump.

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