A rapid hydrogenation system with high hydrogen utilization rate and a working method thereof

Abstract

The application relates to a high-hydrogen-utilization-rate fast hydrogenation system and a working method thereof. The system comprises parallel multi-stage hydrogen storage bottle groups arranged at a station end, each hydrogen storage bottle group is connected with a first switch valve and a second switch valve, each first switch valve is directly connected with a pressure reducing valve, each second switch valve is connected with the pressure reducing valve through a compressor, one end of the pressure reducing valve is connected with a vehicle-mounted hydrogen storage bottle group at a vehicle end through a heat exchanger, and the heat exchanger is connected with a cooling module. The working method of the system is to realize grading and standby direct filling hydrogenation by using the multi-stage hydrogen storage bottle groups and the compressor, and the cooling module can be used for precooling work by using a booster pump and double cooling liquid tanks. Compared with the prior art, the application can guarantee the hydrogenation rate, improve the hydrogen utilization rate, and further guarantee the rapid precooling of high-flow hydrogen in the fast hydrogenation process.

Description

Technical Field

[0001] This invention relates to the field of rapid hydrogenation technology, and in particular to a rapid hydrogenation system with high hydrogen utilization rate and its operating method. Background Technology

[0002] Hydrogen energy, as a clean and efficient secondary energy source, is of great significance for building a clean, low-carbon, safe, and efficient energy system. In the railway transportation industry, although electric trains have significantly reduced the environmental problems caused by fuel-powered trains, the pollution from thermal power generation and the electromagnetic pollution from electric trains cannot be ignored. Therefore, hydrogen-powered trains have become an important direction for the development of rail vehicles. Hydrogen refueling stations, as facilities for hydrogen energy supply, are a crucial link in the hydrogen energy industry. Skid-mounted hydrogen refueling stations have advantages such as mobility, large service radius, and wide coverage, making them more suitable for meeting train operation requirements and thus more ideal for hydrogen-powered train applications. For example, in 2018, Alstom built a mobile hydrogen refueling station to provide temporary hydrogen refueling services for the Coradia iLint train during testing; in 2023, Deutsche Bahn (Germany) developed a mobile rapid refueling system for the Mireo PlusH hydrogen-powered train, capable of refueling 180 kg of hydrogen in 15 minutes.

[0003] While domestic research has comprehensively explored rapid hydrogen refueling strategies for fuel cell vehicles, there is a lack of research specifically on hydrogen refueling stations for trains. Hydrogen-powered trains, depending on their formation and usage scenarios, typically carry 180–500 kg of hydrogen onboard, nearly 3–10 times that of heavy-duty vehicles. During refueling, high-pressure hydrogen is driven by the pressure difference between the station's hydrogen storage system and the onboard hydrogen storage system. The station's hydrogen storage pressure gradually decreases as hydrogen mass is transferred, stopping refueling when it falls below the onboard hydrogen storage pressure. Therefore, the greater the refueling demand, the higher the requirement for the quality of the station's hydrogen storage. To ensure refueling demand, the volume of high-pressure hydrogen provided by the station's hydrogen storage system increases dramatically, leading to a significant increase in the number of hydrogen storage cylinders required and the cost. Simultaneously, the larger volume of the hydrogen storage cylinders makes it difficult to integrate refueling components within a limited enclosed space, thus increasing the design difficulty of skid-mounted hydrogen refueling stations. Furthermore, the significantly increased pre-cooling power due to the substantial increase in refueling flow rate necessitates higher cooling capacity requirements for the refrigeration unit, significantly increasing costs; and the long refrigeration cycle response time makes it difficult to meet the rapid pre-cooling requirements of large-flow hydrogen.

[0004] For example, the invention patent with publication number CN111365607B discloses a three-stage hydrogen refueling method for on-board hydrogen cylinders based on intelligent prediction and control. This method uses a three-stage hydrogen storage cylinder group, and a pre-cooling system ensures the feasibility and safety of hydrogen refueling. The method uses a hydrogen refueling machine as an intelligent control integration center, working in conjunction with temperature, pressure, and communication sensors. The hydrogen refueling machine calculates the refueling scheme based on the initial state information collected by the sensors and controls the refueling process in real time, achieving safe and efficient hydrogen refueling. However, the hydrogen refueling strategy disclosed in this method has low hydrogen utilization, is difficult to pre-cool, and has complex control, making it difficult to meet the requirements of large-capacity rapid hydrogen refueling for trains and thus limiting its widespread application. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art by providing a rapid hydrogen refueling system with high hydrogen utilization and its operating method.

[0006] The objective of this invention can be achieved through the following technical solutions:

[0007] According to one aspect of the present invention, a rapid hydrogen refueling system with high hydrogen utilization rate is provided, comprising a parallel multi-stage hydrogen storage cylinder group installed at the station end, wherein each stage of the hydrogen storage cylinder group is connected to a first switching valve and a second switching valve; wherein each first switching valve is directly connected to a pressure reducing valve 14, and each second switching valve is connected to the pressure reducing valve 14 after passing through a compressor 13; the other end of the pressure reducing valve 14 is connected to an on-board hydrogen storage cylinder group 19 at the vehicle end via a heat exchanger 15.

[0008] As a preferred technical solution, the multi-stage hydrogen storage cylinder group includes: a primary hydrogen storage cylinder group (1), a secondary hydrogen storage cylinder group (2), a tertiary hydrogen storage cylinder group (3), and a quaternary hydrogen storage cylinder group (4).

[0009] As a preferred technical solution, both the multi-stage hydrogen storage tank group and the vehicle-mounted hydrogen storage tank group 19 are equipped with pressure sensors to collect the pressure of the hydrogen storage tank group.

[0010] As a preferred technical solution, the heat exchanger 15 is also connected to a cooling module, which includes a booster pump 18, a first coolant tank 17, and a second coolant tank 16; wherein, the first coolant tank 17 is used to output coolant to complete the cooling work, and the second coolant tank 16 is used to recover coolant.

[0011] As a preferred technical solution, the heat exchanger 15 is equipped with two gas ports and two liquid ports. The first gas port is connected to the pressure reducing valve 14, the second gas port is connected to the on-board hydrogen storage tank group 19, the first liquid port is connected to the first coolant tank 17 via the booster pump 18, and the second liquid port is connected to the second coolant tank 16.

[0012] According to another aspect of the present invention, a rapid hydrogen refueling method with high hydrogen utilization is provided. This method is applied to a rapid hydrogen refueling system with high hydrogen utilization as described above. The method utilizes a multi-stage hydrogen storage cylinder group and a compressor 13 to achieve staged and standby direct-charge hydrogen refueling.

[0013] As a preferred technical solution, the process of tiered and standby direct-charge hydrogen refueling includes first to fourth stage refueling and standby refueling. The first to fourth stage refueling is carried out in sequence. If the pressure in the on-board hydrogen storage cylinder group 19 reaches the preset target refueling pressure after the fourth stage refueling is completed, the hydrogen refueling process is completed. If it does not reach the target pressure, standby refueling continues.

[0014] During the first stage of refueling, the first stage first switch valve 5 is opened, and the high-pressure hydrogen in the first stage hydrogen storage cylinder group 1 enters the on-board hydrogen storage cylinder group 19 through the pressure reducing valve 14 and heat exchanger 15 until the pressure difference requirement is reached. The first stage of refueling is then completed, and the first stage first switch valve 5 is closed.

[0015] During the secondary refueling process, the first-stage second switch valve 6 and the second-stage first switch valve 7 are opened. The remaining hydrogen in the first-stage hydrogen storage cylinder group 1 is pressurized by the compressor 13 and then enters the on-board hydrogen storage cylinder group 19 together with the high-pressure hydrogen in the second-stage hydrogen storage cylinder group 2 through the pressure reducing valve 14 and the heat exchanger 15 until the pressure difference requirement is reached. The secondary refueling process ends, and the first-stage second switch valve 6 and the second-stage first switch valve 7 are closed.

[0016] During the three-stage refueling process, the second-stage switch valve 8 and the first-stage switch valve 9 are opened. The remaining hydrogen in the second-stage hydrogen storage cylinder group 2 is pressurized by the compressor 13 and then enters the on-board hydrogen storage cylinder group 19 together with the high-pressure hydrogen in the third-stage hydrogen storage cylinder group 3 through the pressure reducing valve 14 and the heat exchanger 15 until the pressure difference requirement is reached. The three-stage refueling process ends, and the second-stage switch valve 8 and the first-stage switch valve 9 are closed.

[0017] During the fourth-stage refueling, the third-stage second switch valve 10 and the fourth-stage first switch valve 11 are opened. The remaining hydrogen in the third-stage hydrogen storage cylinder group 3 is pressurized by the compressor 13 and then enters the vehicle-mounted hydrogen storage cylinder group 19 together with the high-pressure hydrogen in the fourth-stage hydrogen storage cylinder group 4 through the pressure reducing valve 14 and the heat exchanger 15 until the pressure difference requirement is reached. The fourth-stage refueling ends, and the third-stage second switch valve 10 and the fourth-stage first switch valve 11 are closed.

[0018] During standby refueling, the fourth-stage second switch valve 12 is opened. The remaining hydrogen in the fourth-stage hydrogen storage cylinder group 4 is pressurized by the compressor 13, and then enters the vehicle-mounted hydrogen storage cylinder group 19 through the pressure reducing valve 14 and the heat exchanger 15 until the pressure in the vehicle-mounted hydrogen storage cylinder group 19 reaches the preset target refueling pressure. The standby refueling ends, and the fourth-stage second switch valve 12 is closed.

[0019] The pressure difference requirement is that the pressure difference between the station end and the vehicle end is less than or equal to the preset pressure difference ΔP.

[0020] According to another aspect of the present invention, a rapid hydrogen precooling method with high hydrogen utilization is provided. The method is applied to a rapid hydrogen refueling system with high hydrogen utilization as described above. The method utilizes a booster pump 18, a first coolant tank 17, and a second coolant tank 16 to achieve rapid precooling of hydrogen during the hydrogen refueling process.

[0021] As a preferred technical solution, the process of rapid pre-cooling of hydrogen during hydrogen refueling includes: after the refueling begins, the coolant in the first coolant tank 17 is pressurized by the booster pump 18 and flows into the heat exchanger 15. After the coolant exchanges heat with the hydrogen at the heat exchanger 15, it flows into the second coolant tank 16 for recovery until the refueling is completed.

[0022] As a preferred technical solution, the speed of the booster pump 18 during cooling is adjusted according to the inlet temperature of the on-board hydrogen storage tank group 19.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] 1. The system of this invention includes a parallel multi-stage hydrogen storage cylinder group installed at the station end. Each stage of the hydrogen storage cylinder group is connected to a first switching valve and a second switching valve. Each first switching valve is directly connected to a pressure reducing valve 14, and each second switching valve is connected to the pressure reducing valve 14 after passing through a compressor 13. The other end of the pressure reducing valve 14 is connected to the on-board hydrogen storage cylinder group 19 at the vehicle end via a heat exchanger 15. This invention simultaneously uses both the hydrogen storage cylinder group filling method and the compressor 13 direct filling method to add hydrogen, thereby improving hydrogen utilization while ensuring the hydrogen filling rate.

[0025] 2. This invention connects the heat exchanger 15 to a cooling module, which includes a booster pump 18, a first coolant tank 17, and a second coolant tank 16. The first coolant tank 17 outputs coolant to complete the cooling operation, while the second coolant tank 16 recovers the coolant. This invention uses the booster pump 18 and two coolant tanks together for cooling, pre-storing coolant in the tanks and then supplying it with the booster pump. This makes it easier to achieve the power output required for high-flow hydrogen refueling and ensures rapid pre-cooling of large-flow hydrogen during rapid hydrogen refueling.

[0026] 3. In this invention, by using a compressor, the remaining hydrogen in the hydrogen storage cylinder that cannot be further added by pressure difference can be utilized, thereby improving the hydrogen utilization rate. Because the hydrogen utilization rate is improved, the volume of the hydrogen storage cylinder is reduced when adding the same amount of hydrogen, thus reducing the footprint of the hydrogen storage cylinder and lowering the cost.

[0027] 4. In the first to fourth stage refueling process of this invention, whenever the pressure difference between the station end and the vehicle end is less than or equal to the preset pressure difference ΔP, the current refueling process ends. By setting the preset pressure difference ΔP, the refueling rate is maintained, ensuring that the refueling can be completed within the specified time.

[0028] 5. The pre-cooling process of this invention is as follows: After refueling begins, the coolant in the first coolant tank 17 is pressurized by the booster pump 18 and flows into the heat exchanger 15. After exchanging heat with hydrogen at the heat exchanger 15, the coolant flows into the second coolant tank 16 for recovery until refueling is completed. The speed of the booster pump 18 is adjusted according to the inlet temperature of the on-board hydrogen storage cylinder group 19, which can maintain a constant pre-cooling temperature in real time, ensuring good cooling performance of the system. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of a rapid hydrogenation system with high hydrogen utilization rate according to the present invention.

[0030] Figure 2 This is a flowchart of a rapid hydrogenation method with high hydrogen utilization rate according to the present invention;

[0031] In the diagram, 1 represents the primary hydrogen storage tank assembly, 2 the secondary hydrogen storage tank assembly, 3 the tertiary hydrogen storage tank assembly, 4 the quaternary hydrogen storage tank assembly, 5 the primary first switching valve, 6 the primary second switching valve, 7 the secondary first switching valve, 8 the secondary second switching valve, 9 the tertiary first switching valve, 10 the tertiary second switching valve, 11 the quaternary first switching valve, 12 the quaternary second switching valve, 13 the compressor, 14 the pressure reducing valve, 15 the heat exchanger, 16 the second cooling tank, 17 the first cooling tank, 18 the booster pump, and 19 the on-board hydrogen storage tank assembly. Detailed Implementation

[0032] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0033] Hydrogen energy, as a clean and efficient secondary energy source, is of great significance for building a clean, low-carbon, safe, and efficient energy system. In the railway transportation industry, although electric trains have significantly reduced the environmental problems caused by fuel-powered trains, the pollution from thermal power generation and the electromagnetic pollution from electric trains cannot be ignored. Therefore, hydrogen-powered trains have become an important direction for the development of rail vehicles. Hydrogen refueling stations, as facilities for hydrogen energy supply, are a crucial link in the hydrogen energy industry. Skid-mounted hydrogen refueling stations have advantages such as mobility, large service radius, and wide coverage, making them more suitable for meeting train operation requirements and thus more ideal for hydrogen-powered train applications. For example, in 2018, Alstom built a mobile hydrogen refueling station to provide temporary hydrogen refueling services for the Coradia iLint train during testing; in 2023, Deutsche Bahn (Germany) developed a mobile rapid refueling system for the Mireo PlusH hydrogen-powered train, capable of refueling 180 kg of hydrogen in 15 minutes.

[0034] Currently, domestic technology has comprehensively researched rapid hydrogen refueling strategies for fuel cell vehicles, but research on hydrogen refueling stations for trains is scarce. Hydrogen-powered trains, depending on their formation and usage scenarios, typically have an onboard hydrogen storage capacity of 180–500 kg, nearly 3–10 times that of heavy-duty vehicles. During refueling, high-pressure hydrogen is driven by the pressure difference between the station's hydrogen storage system and the onboard hydrogen storage system. The station's hydrogen storage pressure gradually decreases as hydrogen mass is transferred, stopping refueling when it falls below the onboard hydrogen storage pressure. Therefore, the greater the refueling demand, the higher the requirements for the station's hydrogen storage quality. To ensure refueling demand, the volume of high-pressure hydrogen provided by the station's hydrogen storage system increases dramatically, leading to a significant increase in the number of hydrogen storage cylinders required and costs. Simultaneously, the larger volume of hydrogen storage cylinders makes it difficult to integrate refueling components within a limited enclosed space, thus increasing the design difficulty of skid-mounted hydrogen refueling stations. Furthermore, the significantly increased pre-cooling power due to the substantial increase in refueling flow rate necessitates higher cooling capacity requirements for the refrigeration unit, significantly increasing costs; and the long refrigeration cycle response time makes it difficult to meet the rapid pre-cooling requirements of large-flow hydrogen.

[0035] Therefore, there is an urgent need to develop a rapid hydrogen refueling system and method for trains with high hydrogen utilization.

[0036] Example 1

[0037] In this embodiment, a high-hydrogen-utilization-rate rapid hydrogenation system is used to complete the rapid hydrogenation process. The system structure is as follows: Figure 1 As shown, the system includes a parallel multi-stage hydrogen storage cylinder group installed at the station end. Each stage of the hydrogen storage cylinder group is connected to a first switching valve and a second switching valve. Each first switching valve is directly connected to a pressure reducing valve 14, and each second switching valve is connected to the pressure reducing valve 14 after passing through a compressor 13. The other end of the pressure reducing valve 14 is connected to the vehicle-mounted hydrogen storage cylinder group 19 at the vehicle end via a heat exchanger 15.

[0038] The multi-stage hydrogen storage tank group includes: a primary hydrogen storage tank group (1), a secondary hydrogen storage tank group (2), a tertiary hydrogen storage tank group (3), and a quaternary hydrogen storage tank group (4). Both the multi-stage hydrogen storage tank group and the on-board hydrogen storage tank group (19) are equipped with pressure sensors to collect the pressure of the hydrogen storage tank group.

[0039] The heat exchanger 15 is also connected to a cooling module, which includes a booster pump 18, a first coolant tank 17, and a second coolant tank 16. The first coolant tank 17 is used to output coolant to provide cooling, and the second coolant tank 16 is used to recover coolant. The heat exchanger 15 is equipped with two gas ports and two liquid ports. The first gas port is connected to a pressure reducing valve 14, and the second gas port is connected to an on-board hydrogen storage tank assembly 19. The first liquid port is connected to the first coolant tank 17 via the booster pump 18, and the second liquid port is connected to the second coolant tank 16.

[0040] In this embodiment, a 70MPa train hydrogen refueling station is considered, with a design target of continuously refueling at least 500kg of hydrogen within 30 minutes. The train consists of 4 carriages, and the onboard hydrogen storage system has a water volume of 3.6m³. 3 ×4. A parallel refueling scheme using four hydrogen refueling guns is adopted, meaning each gun is responsible for one 3.6m section of the train car. 3 Refueling of the hydrogen storage subsystem.

[0041] In the following implementation, a rapid hydrogen refueling strategy is designed for a single carriage, and the overall refueling strategy can be replicated based on this.

[0042] In this embodiment, the operating temperature is designed to be 0℃, and the hydrogen density is calculated according to GB / T 31138—2022. The volume of a single 90MPa hydrogen storage cylinder is 0.5m³. 3 Ten 90MPa hydrogen storage cylinders are used for refueling a single carriage. Cylinder groups 1-4 consist of 5, 2, 2, and 1 cylinders respectively, with a total volume of 5m³. 3 A 90MPa compressor 13 was selected, with the minimum inlet pressure set to 20MPa. The hydrogen addition flow rate was controlled by the pressure reducing valve 14 to meet the design target of 500kg / 30min / 4 = 4.17 (kg / min).

[0043] In this embodiment, the pressure of the first to fourth stage hydrogen storage cylinder groups is 90 MPa, divided into first to fourth stages and a standby refueling. The boosting pressure for each stage is: 0→25, 25→40, 40→55, 55→70 MPa. The required refueling mass for each stage is 68.5, 31.9, 26.8, and 22.9 kg, respectively, and the target refueling time for each stage is 16.4, 7.6, 6.4, and 5.5 min, respectively. The standby refueling pressure, mass, and time are determined according to the actual situation. Before refueling begins, all valves are closed. After refueling begins, the first coolant tank 17 provides coolant flow to cool the hydrogen to -40°C through the booster pump 18. After heat exchange with the high-pressure hydrogen in the heat exchanger 15, the coolant flows into the second coolant tank 16 until refueling is completed.

[0044] In this embodiment, the specific filling process is as follows: Figure 2 As shown.

[0045] First, the first stage of refueling is performed. The first stage first switch valve 5 is opened, and the high-pressure hydrogen in the first stage hydrogen storage cylinder group 1 enters the vehicle-mounted hydrogen storage cylinder group 19 through the pressure reducing valve 14 and the heat exchanger 15. When the pressure difference between the first stage hydrogen storage cylinder group 1 and the vehicle-mounted hydrogen storage cylinder group 19 is less than or equal to the preset pressure difference ΔP, the first stage refueling is completed, and the first stage first switch valve 5 is closed.

[0046] During the refueling process, the pressure of the on-board hydrogen storage cylinder group 19 changes from 0 to 25 MPa, the pressure of the first-stage hydrogen storage cylinder group 1 changes from 90 to 30 MPa, and the mass of hydrogen released is 66.9 kg; after the refueling is completed, the pressure of the remaining compressible hydrogen in the first-stage hydrogen storage cylinder group 1 changes from 30 to 20 MPa, and the mass of the remaining part is 16.2 kg.

[0047] Then, a second-stage refueling process is performed. The first-stage second switch valve 6 and the second-stage first switch valve 7 are opened. The remaining compressible hydrogen in the first-stage hydrogen storage cylinder group 1 is pressurized by the compressor 13 and then merges with the high-pressure hydrogen in the second-stage hydrogen storage cylinder group 2 at the exhaust end of the compressor 13. After passing through the pressure reducing valve 14 and the heat exchanger 15, it enters the on-board hydrogen storage cylinder group 19. When the pressure difference between the second-stage hydrogen storage cylinder group 2 and the on-board hydrogen storage cylinder group 19 is less than or equal to the preset pressure difference ΔP, the second-stage refueling is completed, and the first-stage second switch valve 6 and the second-stage first switch valve 7 are closed.

[0048] During the refueling process, the pressure change of the on-board hydrogen storage tank group 19 is 25→40MPa, and the pressure change of the secondary hydrogen storage tank 2 is 90→45MPa, with a released hydrogen mass of 18.4kg. When the initial intake pressure of the 90MPa compressor 13 is 30MPa (residual pressure after primary refueling), the average displacement is 1500Nm. 3 / h. Therefore, within 7.6 minutes, the discharge volume of compressor 13 is 17.2 kg, which is greater than the compressible hydrogen mass of 16.2 kg in the first-stage hydrogen storage tank group 1. This indicates that compressor 13 has sufficient capacity to fully utilize the remaining compressible hydrogen in the first-stage hydrogen storage tank group 1. Furthermore, if compressor 13 and the hydrogen storage tank group are simultaneously added for 7.6 minutes, 34.6 kg can be added, exceeding the required amount of 31.9 kg. After the addition is completed, the pressure of the remaining compressible hydrogen in the second-stage hydrogen storage tank group 2 is: 45→20 MPa, and the remaining mass is 14.8 kg.

[0049] Then, a three-stage refueling process is performed. The second-stage switch valve 8 and the first-stage switch valve 9 are opened. The remaining compressible hydrogen in the second-stage hydrogen storage tank group 2 is pressurized by the compressor 13 and then merges with the high-pressure hydrogen in the third-stage hydrogen storage tank group 3 at the exhaust end of the compressor 13. After passing through the pressure reducing valve 14 and the heat exchanger 15, it enters the on-board hydrogen storage tank group 19. When the pressure difference between the third-stage hydrogen storage tank group 3 and the on-board hydrogen storage tank group 19 is less than or equal to the preset pressure difference ΔP, the three-stage refueling is completed, and the second-stage switch valve 8 and the first-stage switch valve 9 are closed.

[0050] During the refueling process, the pressure change of the on-board hydrogen storage tank group 19 is 40→55MPa, and the pressure change of the three-stage hydrogen storage tank group 3 is 90→60MPa, with a released hydrogen mass of 11.4kg. When the initial intake pressure of the 90MPa compressor 13 is 45MPa (residual pressure after secondary refueling), the average displacement is 2000Nm. 3 / h. Therefore, within 6.4 minutes, the discharge volume of compressor 13 is 19.3 kg, which is greater than the compressible hydrogen mass of 14.8 kg. This indicates that compressor 13 has sufficient capacity to fully utilize the remaining compressible hydrogen in the secondary hydrogen storage tank group 2. Furthermore, with compressor 13 and the hydrogen storage tank group simultaneously adding fuel for 6.4 minutes, 26.2 kg can be added, slightly less than the required fuel mass of 26.8 kg. After fueling is completed, the pressure of the remaining compressible hydrogen in the tertiary hydrogen storage tank group 3 is 60→20 MPa, and the remaining mass is 21.9 kg.

[0051] Finally, the fourth-stage refueling is performed. The third-stage second switch valve 10 and the fourth-stage first switch valve 11 are opened. The remaining compressible hydrogen in the third-stage hydrogen storage cylinder group 3 is pressurized by the compressor 13 and then merges with the high-pressure hydrogen in the fourth-stage hydrogen storage cylinder group 4 at the exhaust end of the compressor 13. After passing through the pressure reducing valve 14 and the heat exchanger 15, it enters the on-board hydrogen storage cylinder group 19. When the pressure difference between the fourth-stage hydrogen storage cylinder group 4 and the on-board hydrogen storage cylinder group 19 is less than or equal to the preset pressure difference ΔP, the fourth-stage refueling is completed, and the third-stage second switch valve 10 and the fourth-stage first switch valve 11 are closed.

[0052] During the refueling process, the pressure change of the on-board hydrogen storage tank group 19 is 55→70MPa, and the pressure change of the fourth-stage hydrogen storage tank group 4 is 90→75MPa, with a released hydrogen mass of 2.7kg; when the initial intake pressure of the compressor 13 is 60MPa (the remaining pressure after the third-stage refueling), the average displacement is 2500Nm. 3 / h. Therefore, within 5.5 minutes, the discharge volume of compressor 13 is 20.6 kg, which is less than the compressible hydrogen mass of 21.86 kg. This indicates that compressor 13 can only utilize 20.6 kg of hydrogen. Furthermore, compressor 13 and the hydrogen storage tank group can simultaneously add 23.3 kg in 5.5 minutes, exceeding the required addition mass. After addition is complete, the remaining compressible hydrogen pressure in the four-stage hydrogen storage tank group 4 is 75→20 MPa, and the remaining mass is 21.9 kg. This portion of hydrogen will serve as a backup hydrogen source, to be utilized by compressor 13 if the target addition pressure is not reached.

[0053] After the four-stage refueling process is completed, the remaining hydrogen masses in each stage of the hydrogen storage cylinder group are 39.22, 15.69, 16.9, and 21.8 kg, respectively, and the total hydrogen storage capacity of the four stages is 122.3, 48.9, 48.9, and 24.5 kg, respectively. Therefore, the hydrogen utilization rates for each stage are 67.9%, 67.9%, 65.4%, and 11.0%, respectively, with a total hydrogen utilization rate of 61.7%. It can be seen that the hydrogen utilization rate of the fourth stage refueling is the lowest. Therefore, the hydrogen utilization rate of the fourth-stage hydrogen storage cylinder group 4 can be improved by using a backup refueling process. For example, if the backup refueling is used to continue refueling the on-board hydrogen storage cylinder group 19 to 75 MPa, the hydrogen utilization rate of the fourth-stage hydrogen storage cylinder group 4 will increase to 39.4%, and the total hydrogen utilization rate will increase to 64.6%. The extra refueling time can be adjusted by the pressure reducing valve 14, ensuring that the total refueling time does not exceed 30 minutes.

[0054] In this embodiment, the preset pressure difference ΔP is 5 MPa.

[0055] In summary, the high-capacity rapid hydrogen refueling system with high hydrogen utilization rate used in this embodiment includes a parallel multi-stage hydrogen storage cylinder group installed at the station end. Each stage of the hydrogen storage cylinder group is connected to a first switching valve and a second switching valve. Each first switching valve is directly connected to a pressure reducing valve 14, and each second switching valve is connected to the pressure reducing valve 14 after passing through a compressor 13. The other end of the pressure reducing valve 14 is connected to the on-board hydrogen storage cylinder group 19 at the vehicle end via a heat exchanger 15. Simultaneously using the hydrogen storage cylinder group refueling method and the compressor 13 direct charging method for hydrogen refueling improves hydrogen utilization rate while ensuring the hydrogen refueling rate.

[0056] The system's cooling module includes a heat exchanger 15, a booster pump 18, a first coolant tank 17, and a second coolant tank 16. The first coolant tank 17 outputs coolant to complete the cooling operation, while the second coolant tank 16 recovers the coolant. This invention uses the booster pump 18 and two coolant tanks together for cooling, pre-storing coolant in the tanks and then supplying it with the booster pump. This makes it easier to achieve the power output required for high-flow hydrogen refueling and ensures rapid pre-cooling of large-flow hydrogen during rapid hydrogen refueling.

[0057] Example 2

[0058] In this embodiment, a rapid hydrogen refueling method with high hydrogen utilization rate is applied to complete the rapid hydrogen refueling operation. This method is applied to a rapid hydrogen refueling system with high hydrogen utilization rate. The method utilizes a multi-stage hydrogen storage cylinder group and compressor 13 to achieve staged and standby direct charging of hydrogen.

[0059] The process of tiered and standby direct-charge hydrogen refueling includes first to fourth stage refueling and standby refueling. The first to fourth stage refueling is carried out in sequence. If the pressure in the on-board hydrogen storage cylinder group 19 reaches the preset target refueling pressure after the fourth stage refueling is completed, the hydrogen refueling process is completed. If it does not reach the target pressure, standby refueling continues.

[0060] During the first stage of refueling, the first stage first switch valve 5 is opened. The high-pressure hydrogen in the first stage hydrogen storage cylinder group 1 enters the on-board hydrogen storage cylinder group 19 through the pressure reducing valve 14 and heat exchanger 15 until the pressure difference requirement is reached. The first stage of refueling is then completed and the first stage first switch valve 5 is closed.

[0061] During secondary refueling, the first-stage second switch valve 6 and the second-stage first switch valve 7 are opened. The remaining hydrogen in the first-stage hydrogen storage cylinder group 1 is pressurized by the compressor 13 and then enters the on-board hydrogen storage cylinder group 19 together with the high-pressure hydrogen in the second-stage hydrogen storage cylinder group 2 through the pressure reducing valve 14 and the heat exchanger 15 until the pressure difference requirement is reached. The second-stage refueling ends, and the first-stage second switch valve 6 and the second-stage first switch valve 7 are closed.

[0062] During the third-stage refueling, the second-stage second switch valve 8 and the third-stage first switch valve 9 are opened. The remaining hydrogen in the second-stage hydrogen storage cylinder group 2 is pressurized by the compressor 13 and then enters the on-board hydrogen storage cylinder group 19 together with the high-pressure hydrogen in the third-stage hydrogen storage cylinder group 3 through the pressure reducing valve 14 and the heat exchanger 15 until the pressure difference requirement is reached. The third-stage refueling is then completed, and the second-stage second switch valve 8 and the third-stage first switch valve 9 are closed.

[0063] During the fourth-stage refueling, the third-stage second switch valve 10 and the fourth-stage first switch valve 11 are opened. The remaining hydrogen in the third-stage hydrogen storage cylinder group 3 is pressurized by the compressor 13 and then enters the on-board hydrogen storage cylinder group 19 together with the high-pressure hydrogen in the fourth-stage hydrogen storage cylinder group 4 through the pressure reducing valve 14 and the heat exchanger 15 until the pressure difference requirement is reached. The fourth-stage refueling is then completed, and the third-stage second switch valve 10 and the fourth-stage first switch valve 11 are closed.

[0064] When refueling, the fourth-stage second switch valve 12 is opened. The remaining hydrogen in the fourth-stage hydrogen storage cylinder group 4 is pressurized by the compressor 13, and then enters the vehicle-mounted hydrogen storage cylinder group 19 through the pressure reducing valve 14 and the heat exchanger 15 until the pressure in the vehicle-mounted hydrogen storage cylinder group 19 reaches the preset target refueling pressure. The standby refueling ends and the fourth-stage second switch valve 12 is closed.

[0065] The pressure difference requirement is that the pressure difference between the station end and the vehicle end is less than or equal to the preset pressure difference ΔP.

[0066] In this embodiment, a 70MPa train hydrogen refueling station is considered, with a design target of continuously refueling at least 500kg of hydrogen within 30 minutes. The train consists of 4 carriages, and the onboard hydrogen storage system has a water volume of 3.6m³. 3 ×4. A parallel refueling scheme using four hydrogen refueling nozzles is adopted, meaning each nozzle is responsible for one 3.6m section of the train car. 3 Refueling of the hydrogen storage subsystem.

[0067] In the following implementation, a rapid hydrogen refueling strategy is designed for a single carriage, and the overall refueling strategy can be replicated based on this.

[0068] In this embodiment, the operating temperature is designed to be 0℃, and the hydrogen density is calculated according to GB / T 31138—2022. The volume of a single 90MPa hydrogen storage cylinder is 0.5m³. 3 Ten 90MPa hydrogen storage cylinders are used for refueling a single carriage. Cylinder groups 1-4 consist of 5, 2, 2, and 1 cylinders respectively, with a total volume of 5m³. 3 A 90MPa compressor 13 was selected, with the minimum inlet pressure set to 20MPa. The hydrogen addition flow rate was controlled by the pressure reducing valve 14 to meet the design target of 500kg / 30min / 4 = 4.17 (kg / min).

[0069] In this embodiment, the pressure of the first to fourth stage hydrogen storage cylinder groups is 90 MPa, divided into first to fourth stages and a standby refueling. The boosting pressure for each stage is: 0→25, 25→40, 40→55, 55→70 MPa. The required refueling mass for each stage is 68.5, 31.9, 26.8, and 22.9 kg, respectively, and the target refueling time for each stage is 16.4, 7.6, 6.4, and 5.5 min, respectively. The standby refueling pressure, mass, and time are determined according to the actual situation. Before refueling begins, all valves are closed. After refueling begins, the first coolant tank 17 provides coolant flow to cool the hydrogen to -40°C through the booster pump 18. After heat exchange with the high-pressure hydrogen in the heat exchanger 15, the coolant flows into the second coolant tank 16 until refueling is completed.

[0070] In this embodiment, the specific filling process is as follows: Figure 2 As shown.

[0071] First, the first stage of refueling is performed. The first stage first switch valve 5 is opened, and the high-pressure hydrogen in the first stage hydrogen storage cylinder group 1 enters the vehicle-mounted hydrogen storage cylinder group 19 through the pressure reducing valve 14 and the heat exchanger 15. When the pressure difference between the first stage hydrogen storage cylinder group 1 and the vehicle-mounted hydrogen storage cylinder group 19 is less than or equal to the preset pressure difference ΔP, the first stage refueling is completed, and the first stage first switch valve 5 is closed.

[0072] During the refueling process, the pressure of the on-board hydrogen storage cylinder group 19 changes from 0 to 25 MPa, the pressure of the first-stage hydrogen storage cylinder group 1 changes from 90 to 30 MPa, and the mass of hydrogen released is 66.9 kg; after the refueling is completed, the pressure of the remaining compressible hydrogen in the first-stage hydrogen storage cylinder group 1 changes from 30 to 20 MPa, and the mass of the remaining part is 16.2 kg.

[0073] Then, a second-stage refueling process is performed. The first-stage second switch valve 6 and the second-stage first switch valve 7 are opened. The remaining compressible hydrogen in the first-stage hydrogen storage cylinder group 1 is pressurized by the compressor 13 and then merges with the high-pressure hydrogen in the second-stage hydrogen storage cylinder group 2 at the exhaust end of the compressor 13. After passing through the pressure reducing valve 14 and the heat exchanger 15, it enters the on-board hydrogen storage cylinder group 19. When the pressure difference between the second-stage hydrogen storage cylinder group 2 and the on-board hydrogen storage cylinder group 19 is less than or equal to the preset pressure difference ΔP, the second-stage refueling is completed, and the first-stage second switch valve 6 and the second-stage first switch valve 7 are closed.

[0074] During the refueling process, the pressure change of the on-board hydrogen storage tank group 19 is 25→40MPa, and the pressure change of the secondary hydrogen storage tank 2 is 90→45MPa, with a released hydrogen mass of 18.4kg. When the initial intake pressure of the 90MPa compressor 13 is 30MPa (residual pressure after primary refueling), the average displacement is 1500Nm. 3 / h. Therefore, within 7.6 minutes, the discharge volume of compressor 13 is 17.2 kg, which is greater than the compressible hydrogen mass of 16.2 kg in the first-stage hydrogen storage tank group 1. This indicates that compressor 13 has sufficient capacity to fully utilize the remaining compressible hydrogen in the first-stage hydrogen storage tank group 1. Furthermore, if compressor 13 and the hydrogen storage tank group are simultaneously added for 7.6 minutes, 34.6 kg can be added, exceeding the required amount of 31.9 kg. After the addition is completed, the pressure of the remaining compressible hydrogen in the second-stage hydrogen storage tank group 2 is: 45→20 MPa, and the remaining mass is 14.8 kg.

[0075] Then, a three-stage refueling process is performed. The second-stage switch valve 8 and the first-stage switch valve 9 are opened. The remaining compressible hydrogen in the second-stage hydrogen storage tank group 2 is pressurized by the compressor 13 and then merges with the high-pressure hydrogen in the third-stage hydrogen storage tank group 3 at the exhaust end of the compressor 13. After passing through the pressure reducing valve 14 and the heat exchanger 15, it enters the on-board hydrogen storage tank group 19. When the pressure difference between the third-stage hydrogen storage tank group 3 and the on-board hydrogen storage tank group 19 is less than or equal to the preset pressure difference ΔP, the three-stage refueling is completed, and the second-stage switch valve 8 and the first-stage switch valve 9 are closed.

[0076] During the refueling process, the pressure change of the on-board hydrogen storage tank group 19 is 40→55MPa, and the pressure change of the three-stage hydrogen storage tank group 3 is 90→60MPa, with a released hydrogen mass of 11.4kg. When the initial intake pressure of the 90MPa compressor 13 is 45MPa (residual pressure after secondary refueling), the average displacement is 2000Nm. 3 / h. Therefore, within 6.4 minutes, the discharge volume of compressor 13 is 19.3 kg, which is greater than the compressible hydrogen mass of 14.8 kg. This indicates that compressor 13 has sufficient capacity to fully utilize the remaining compressible hydrogen in the secondary hydrogen storage tank group 2. Furthermore, with compressor 13 and the hydrogen storage tank group simultaneously adding fuel for 6.4 minutes, 26.2 kg can be added, slightly less than the required fuel mass of 26.8 kg. After fueling is completed, the pressure of the remaining compressible hydrogen in the tertiary hydrogen storage tank group 3 is 60→20 MPa, and the remaining mass is 21.9 kg.

[0077] Finally, the fourth-stage refueling is performed. The third-stage second switch valve 10 and the fourth-stage first switch valve 11 are opened. The remaining compressible hydrogen in the third-stage hydrogen storage cylinder group 3 is pressurized by the compressor 13 and then merges with the high-pressure hydrogen in the fourth-stage hydrogen storage cylinder group 4 at the exhaust end of the compressor 13. After passing through the pressure reducing valve 14 and the heat exchanger 15, it enters the on-board hydrogen storage cylinder group 19. When the pressure difference between the fourth-stage hydrogen storage cylinder group 4 and the on-board hydrogen storage cylinder group 19 is less than or equal to the preset pressure difference ΔP, the fourth-stage refueling is completed, and the third-stage second switch valve 10 and the fourth-stage first switch valve 11 are closed.

[0078] During the refueling process, the pressure change of the on-board hydrogen storage tank group 19 is 55→70MPa, and the pressure change of the fourth-stage hydrogen storage tank group 4 is 90→75MPa, with a released hydrogen mass of 2.7kg; when the initial intake pressure of the compressor 13 is 60MPa (the remaining pressure after the third-stage refueling), the average displacement is 2500Nm. 3 / h. Therefore, within 5.5 minutes, the discharge volume of compressor 13 is 20.6 kg, which is less than the compressible hydrogen mass of 21.86 kg. This indicates that compressor 13 can only utilize 20.6 kg of hydrogen. Furthermore, compressor 13 and the hydrogen storage tank group can simultaneously add 23.3 kg in 5.5 minutes, exceeding the required addition mass. After addition is complete, the remaining compressible hydrogen pressure in the four-stage hydrogen storage tank group 4 is 75→20 MPa, and the remaining mass is 21.9 kg. This portion of hydrogen will serve as a backup hydrogen source, to be utilized by compressor 13 if the target addition pressure is not reached.

[0079] After the four-stage refueling process is completed, the remaining hydrogen masses in each stage of the hydrogen storage cylinder group are 39.22, 15.69, 16.9, and 21.8 kg, respectively, and the total hydrogen storage capacity of the four stages is 122.3, 48.9, 48.9, and 24.5 kg, respectively. Therefore, the hydrogen utilization rates for each stage are 67.9%, 67.9%, 65.4%, and 11.0%, respectively, with a total hydrogen utilization rate of 61.7%. It can be seen that the hydrogen utilization rate of the fourth stage refueling is the lowest. Therefore, the hydrogen utilization rate of the fourth-stage hydrogen storage cylinder group 4 can be improved by using a backup refueling process. For example, if the backup refueling is used to continue refueling the on-board hydrogen storage cylinder group 19 to 75 MPa, the hydrogen utilization rate of the fourth-stage hydrogen storage cylinder group 4 will increase to 39.4%, and the total hydrogen utilization rate will increase to 64.6%. The extra refueling time can be adjusted by the pressure reducing valve 14, ensuring that the total refueling time does not exceed 30 minutes.

[0080] In this embodiment, the preset pressure difference ΔP is 5 MPa.

[0081] In summary, the high-hydrogen-utilization, large-capacity rapid hydrogen refueling method applied in this embodiment utilizes a compressor to improve hydrogen utilization by using the remaining hydrogen in the storage tank that cannot be refueled further due to pressure difference. Because of the improved hydrogen utilization, the volume of the storage tank is reduced when refueling the same amount of hydrogen, thus reducing the footprint and lowering costs. Furthermore, during the first to fourth stages of refueling, the current refueling process ends whenever the pressure difference between the station end and the vehicle end is less than or equal to a preset pressure difference ΔP. By setting the preset pressure difference ΔP, the refueling rate is maintained, ensuring that refueling can be completed within a specified time. This approach improves hydrogen utilization while maintaining the refueling rate.

[0082] Example 3

[0083] In this embodiment, a rapid hydrogen refueling method with high hydrogen utilization is applied to complete the rapid hydrogen refueling operation. This method is applied to a rapid hydrogen refueling system with high hydrogen utilization. The method uses a booster pump 18, a first coolant tank 17 and a second coolant tank 16 to achieve rapid pre-cooling of hydrogen during the hydrogen refueling process.

[0084] During the hydrogen refueling process, the rapid pre-cooling of hydrogen includes the following steps: After refueling begins, the coolant in the first coolant tank 17 is pressurized by the booster pump 18 and flows into the heat exchanger 15. After exchanging heat with the hydrogen at the heat exchanger 15, the coolant flows into the second coolant tank 16 for recovery until refueling is completed. During the cooling process, the speed of the booster pump 18 is adjusted according to the inlet temperature of the on-board hydrogen storage cylinder group 19.

[0085] In this embodiment, a 70MPa train hydrogen refueling station is considered, with a design target of continuously refueling at least 500kg of hydrogen within 30 minutes. The train consists of 4 carriages, and the onboard hydrogen storage system has a water volume of 3.6m³. 3 ×4. A parallel refueling scheme using four hydrogen refueling nozzles is adopted, meaning each nozzle is responsible for one 3.6m section of the train car. 3 Refueling of the hydrogen storage subsystem.

[0086] In the following implementation, a rapid hydrogen refueling strategy is designed for a single carriage, and the overall refueling strategy can be replicated based on this.

[0087] In this embodiment, the operating temperature is designed to be 0℃, and the hydrogen density is calculated according to GB / T 31138—2022. The volume of a single 90MPa hydrogen storage cylinder is 0.5m³. 3 Ten 90MPa hydrogen storage cylinders are used for refueling a single carriage. Cylinder groups 1-4 consist of 5, 2, 2, and 1 cylinders respectively, with a total volume of 5m³. 3 A 90MPa compressor 13 was selected, with the minimum inlet pressure set to 20MPa. The hydrogen addition flow rate was controlled by the pressure reducing valve 14 to meet the design target of 500kg / 30min / 4 = 4.17 (kg / min).

[0088] In this embodiment, the pressure of the first to fourth stage hydrogen storage cylinder groups is 90 MPa, divided into first to fourth stages and a standby refueling. The boosting pressure for each stage is: 0→25, 25→40, 40→55, 55→70 MPa. The required refueling mass for each stage is 68.5, 31.9, 26.8, and 22.9 kg, respectively, and the target refueling time for each stage is 16.4, 7.6, 6.4, and 5.5 min, respectively. The standby refueling pressure, mass, and time are determined according to the actual situation. Before refueling begins, all valves are closed. After refueling begins, the first coolant tank 17 provides coolant flow to cool the hydrogen to -40°C through the booster pump 18. After heat exchange with the high-pressure hydrogen in the heat exchanger 15, the coolant flows into the second coolant tank 16 until refueling is completed.

[0089] In this embodiment, the specific filling process is as follows: Figure 2 As shown.

[0090] First, the first stage of refueling is performed. The first stage first switch valve 5 is opened, and the high-pressure hydrogen in the first stage hydrogen storage cylinder group 1 enters the vehicle-mounted hydrogen storage cylinder group 19 through the pressure reducing valve 14 and the heat exchanger 15. When the pressure difference between the first stage hydrogen storage cylinder group 1 and the vehicle-mounted hydrogen storage cylinder group 19 is less than or equal to the preset pressure difference ΔP, the first stage refueling is completed, and the first stage first switch valve 5 is closed.

[0091] During the refueling process, the pressure of the on-board hydrogen storage cylinder group 19 changes from 0 to 25 MPa, the pressure of the first-stage hydrogen storage cylinder group 1 changes from 90 to 30 MPa, and the mass of hydrogen released is 66.9 kg; after the refueling is completed, the pressure of the remaining compressible hydrogen in the first-stage hydrogen storage cylinder group 1 changes from 30 to 20 MPa, and the mass of the remaining part is 16.2 kg.

[0092] Then, a second-stage refueling process is performed. The first-stage second switch valve 6 and the second-stage first switch valve 7 are opened. The remaining compressible hydrogen in the first-stage hydrogen storage cylinder group 1 is pressurized by the compressor 13 and then merges with the high-pressure hydrogen in the second-stage hydrogen storage cylinder group 2 at the exhaust end of the compressor 13. After passing through the pressure reducing valve 14 and the heat exchanger 15, it enters the on-board hydrogen storage cylinder group 19. When the pressure difference between the second-stage hydrogen storage cylinder group 2 and the on-board hydrogen storage cylinder group 19 is less than or equal to the preset pressure difference ΔP, the second-stage refueling is completed, and the first-stage second switch valve 6 and the second-stage first switch valve 7 are closed.

[0093] During the refueling process, the pressure change of the on-board hydrogen storage tank group 19 is 25→40MPa, and the pressure change of the secondary hydrogen storage tank 2 is 90→45MPa, with a released hydrogen mass of 18.4kg. When the initial intake pressure of the 90MPa compressor 13 is 30MPa (residual pressure after primary refueling), the average displacement is 1500Nm. 3 / h. Therefore, within 7.6 minutes, the discharge volume of compressor 13 is 17.2 kg, which is greater than the compressible hydrogen mass of 16.2 kg in the first-stage hydrogen storage tank group 1. This indicates that compressor 13 has sufficient capacity to fully utilize the remaining compressible hydrogen in the first-stage hydrogen storage tank group 1. Furthermore, if compressor 13 and the hydrogen storage tank group are simultaneously added for 7.6 minutes, 34.6 kg can be added, exceeding the required amount of 31.9 kg. After the addition is completed, the pressure of the remaining compressible hydrogen in the second-stage hydrogen storage tank group 2 is: 45→20 MPa, and the remaining mass is 14.8 kg.

[0094] Then, a three-stage refueling process is performed. The second-stage switch valve 8 and the first-stage switch valve 9 are opened. The remaining compressible hydrogen in the second-stage hydrogen storage tank group 2 is pressurized by the compressor 13 and then merges with the high-pressure hydrogen in the third-stage hydrogen storage tank group 3 at the exhaust end of the compressor 13. After passing through the pressure reducing valve 14 and the heat exchanger 15, it enters the on-board hydrogen storage tank group 19. When the pressure difference between the third-stage hydrogen storage tank group 3 and the on-board hydrogen storage tank group 19 is less than or equal to the preset pressure difference ΔP, the three-stage refueling is completed, and the second-stage switch valve 8 and the first-stage switch valve 9 are closed.

[0095] During the refueling process, the pressure change of the on-board hydrogen storage tank group 19 is 40→55MPa, and the pressure change of the three-stage hydrogen storage tank group 3 is 90→60MPa, with a released hydrogen mass of 11.4kg. When the initial intake pressure of the 90MPa compressor 13 is 45MPa (residual pressure after secondary refueling), the average displacement is 2000Nm. 3 / h. Therefore, within 6.4 minutes, the discharge volume of compressor 13 is 19.3 kg, which is greater than the compressible hydrogen mass of 14.8 kg. This indicates that compressor 13 has sufficient capacity to fully utilize the remaining compressible hydrogen in the secondary hydrogen storage tank group 2. Furthermore, with compressor 13 and the hydrogen storage tank group simultaneously adding fuel for 6.4 minutes, 26.2 kg can be added, slightly less than the required fuel mass of 26.8 kg. After fueling is completed, the pressure of the remaining compressible hydrogen in the tertiary hydrogen storage tank group 3 is 60→20 MPa, and the remaining mass is 21.9 kg.

[0096] Finally, the fourth-stage refueling is performed. The third-stage second switch valve 10 and the fourth-stage first switch valve 11 are opened. The remaining compressible hydrogen in the third-stage hydrogen storage cylinder group 3 is pressurized by the compressor 13 and then merges with the high-pressure hydrogen in the fourth-stage hydrogen storage cylinder group 4 at the exhaust end of the compressor 13. After passing through the pressure reducing valve 14 and the heat exchanger 15, it enters the on-board hydrogen storage cylinder group 19. When the pressure difference between the fourth-stage hydrogen storage cylinder group 4 and the on-board hydrogen storage cylinder group 19 is less than or equal to the preset pressure difference ΔP, the fourth-stage refueling is completed, and the third-stage second switch valve 10 and the fourth-stage first switch valve 11 are closed.

[0097] During the refueling process, the pressure change of the on-board hydrogen storage tank group 19 is 55→70MPa, and the pressure change of the fourth-stage hydrogen storage tank group 4 is 90→75MPa, with a released hydrogen mass of 2.7kg; when the initial intake pressure of the compressor 13 is 60MPa (the remaining pressure after the third-stage refueling), the average displacement is 2500Nm. 3 / h. Therefore, within 5.5 minutes, the discharge volume of compressor 13 is 20.6 kg, which is less than the compressible hydrogen mass of 21.86 kg. This indicates that compressor 13 can only utilize 20.6 kg of hydrogen. Furthermore, compressor 13 and the hydrogen storage tank group can simultaneously add 23.3 kg in 5.5 minutes, exceeding the required addition mass. After addition is complete, the remaining compressible hydrogen pressure in the four-stage hydrogen storage tank group 4 is 75→20 MPa, and the remaining mass is 21.9 kg. This portion of hydrogen will serve as a backup hydrogen source, to be utilized by compressor 13 if the target addition pressure is not reached.

[0098] After the four-stage refueling process is completed, the remaining hydrogen masses in each stage of the hydrogen storage cylinder group are 39.22, 15.69, 16.9, and 21.8 kg, respectively, and the total hydrogen storage capacity of the four stages is 122.3, 48.9, 48.9, and 24.5 kg, respectively. Therefore, the hydrogen utilization rates for each stage are 67.9%, 67.9%, 65.4%, and 11.0%, respectively, with a total hydrogen utilization rate of 61.7%. It can be seen that the hydrogen utilization rate of the fourth stage refueling is the lowest. Therefore, the hydrogen utilization rate of the fourth-stage hydrogen storage cylinder group 4 can be improved by using a backup refueling process. For example, if the backup refueling is used to continue refueling the on-board hydrogen storage cylinder group 19 to 75 MPa, the hydrogen utilization rate of the fourth-stage hydrogen storage cylinder group 4 will increase to 39.4%, and the total hydrogen utilization rate will increase to 64.6%. The extra refueling time can be adjusted by the pressure reducing valve 14, ensuring that the total refueling time does not exceed 30 minutes.

[0099] In this embodiment, the preset pressure difference ΔP is 5 MPa.

[0100] In summary, the high-capacity rapid hydrogen refueling method with high hydrogen utilization rate applied in this embodiment involves the coolant in the first coolant tank 17 being pressurized by the booster pump 18 and flowing into the heat exchanger 15 after refueling begins. After exchanging heat with the hydrogen at the heat exchanger 15, the coolant flows into the second coolant tank 16 for recovery until refueling is complete. The speed of the booster pump 18 is adjusted according to the inlet temperature of the on-board hydrogen storage cylinder group 19 to maintain a pre-cooling temperature of -40°C, ensuring good cooling performance of the system. This method improves hydrogen utilization while ensuring the refueling rate, and its cooling operation also ensures rapid pre-cooling of the large flow of hydrogen during rapid refueling.

[0101] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A rapid hydrogen refueling system with high hydrogen utilization rate, characterized in that, It includes a parallel multi-stage hydrogen storage cylinder group set at the station end, and each stage of the hydrogen storage cylinder group is connected to a first switch valve and a second switch valve; wherein, each first switch valve is directly connected to a pressure reducing valve (14), and each second switch valve is connected to a pressure reducing valve (14) after passing through a compressor (13); the other end of the pressure reducing valve (14) is connected to the vehicle-mounted hydrogen storage cylinder group (19) at the vehicle end through a heat exchanger (15); The multi-stage hydrogen storage cylinder group includes: a primary hydrogen storage cylinder group (1), a secondary hydrogen storage cylinder group (2), a tertiary hydrogen storage cylinder group (3), and a quaternary hydrogen storage cylinder group (4). The remaining hydrogen in the primary hydrogen storage tank group (1) is pressurized by the compressor (13) and then enters the vehicle-mounted hydrogen storage tank group (19) together with the high-pressure hydrogen in the secondary hydrogen storage tank group (2) through the pressure reducing valve (14) and heat exchanger (15). The remaining hydrogen in the secondary hydrogen storage cylinder group (2) is pressurized by the compressor (13) and then enters the vehicle-mounted hydrogen storage cylinder group (19) together with the high-pressure hydrogen in the tertiary hydrogen storage cylinder group (3) through the pressure reducing valve (14) and heat exchanger (15).

2. The rapid hydrogen refueling system with high hydrogen utilization rate according to claim 1, characterized in that, The multi-stage hydrogen storage cylinder group and the vehicle-mounted hydrogen storage cylinder group (19) are both equipped with pressure sensors to collect the pressure of the hydrogen storage cylinder group.

3. The rapid hydrogen refueling system with high hydrogen utilization rate according to claim 1, characterized in that, The heat exchanger (15) is also connected to a cooling module, which includes a booster pump (18), a first coolant tank (17), and a second coolant tank (16); wherein the first coolant tank (17) is used to output coolant to complete the cooling work, and the second coolant tank (16) is used to recover coolant.

4. The rapid hydrogen refueling system with high hydrogen utilization rate according to claim 3, characterized in that, The heat exchanger (15) is equipped with two gas ports and two liquid ports. The first gas port is connected to a pressure reducing valve (14), the second gas port is connected to a vehicle-mounted hydrogen storage tank group (19), the first liquid port is connected to a first coolant tank (17) via a booster pump (18), and the second liquid port is connected to a second coolant tank (16).

5. A rapid hydrogenation method with high hydrogen utilization rate, characterized in that, This method is applied to a high hydrogen utilization rate rapid hydrogen refueling system as described in any one of claims 1-4. This method utilizes a multi-stage hydrogen storage cylinder group and a compressor (13) to achieve staged and standby direct refueling of hydrogen.

6. The rapid hydrogenation method with high hydrogen utilization rate according to claim 5, characterized in that, The process of tiered and standby direct-charge hydrogen refueling includes first to fourth stage refueling and standby refueling. The first to fourth stage refueling is carried out in sequence. If the pressure in the on-board hydrogen storage cylinder group (19) reaches the preset target refueling pressure after the fourth stage refueling is completed, the hydrogen refueling process is completed. If it does not reach the target pressure, standby refueling continues. During the first stage of refueling, the first stage first switch valve (5) is opened, and the high-pressure hydrogen in the first stage hydrogen storage cylinder group (1) enters the vehicle-mounted hydrogen storage cylinder group (19) through the pressure reducing valve (14) and heat exchanger (15) until the pressure difference requirement is reached. The first stage of refueling ends and the first stage first switch valve (5) is closed. During the secondary refueling, the first-stage second switch valve (6) and the second-stage first switch valve (7) are opened. The remaining hydrogen in the first-stage hydrogen storage cylinder group (1) is pressurized by the compressor (13) and then enters the vehicle-mounted hydrogen storage cylinder group (19) together with the high-pressure hydrogen in the second-stage hydrogen storage cylinder group (2) through the pressure reducing valve (14) and the heat exchanger (15) until the pressure difference requirement is reached. The secondary refueling ends, and the first-stage second switch valve (6) and the second-stage first switch valve (7) are closed. During the three-stage refueling process, the second-stage switch valve (8) and the first-stage switch valve (9) are opened. The remaining hydrogen in the second-stage hydrogen storage cylinder group (2) is pressurized by the compressor (13) and then enters the on-board hydrogen storage cylinder group (19) together with the high-pressure hydrogen in the third-stage hydrogen storage cylinder group (3) through the pressure reducing valve (14) and the heat exchanger (15) until the pressure difference requirement is reached. The three-stage refueling process ends, and the second-stage switch valve (8) and the first-stage switch valve (9) are closed. During the fourth-stage refueling, the third-stage second switch valve (10) and the fourth-stage first switch valve (11) are opened. The remaining hydrogen in the third-stage hydrogen storage cylinder group (3) is pressurized by the compressor (13) and then enters the vehicle-mounted hydrogen storage cylinder group (19) together with the high-pressure hydrogen in the fourth-stage hydrogen storage cylinder group (4) through the pressure reducing valve (14) and the heat exchanger (15) until the pressure difference requirement is reached. The fourth-stage refueling ends, and the third-stage second switch valve (10) and the fourth-stage first switch valve (11) are closed. During the standby refueling, the fourth-stage second switch valve (12) is opened. The remaining hydrogen in the fourth-stage hydrogen storage cylinder group (4) is pressurized by the compressor (13), and then enters the vehicle-mounted hydrogen storage cylinder group (19) through the pressure reducing valve (14) and heat exchanger (15) until the pressure in the vehicle-mounted hydrogen storage cylinder group (19) reaches the preset target refueling pressure. The standby refueling ends and the fourth-stage second switch valve (12) is closed. The pressure difference requirement is: the pressure difference between the station terminal and the vehicle terminal is less than or equal to the preset pressure difference. .

7. A rapid hydrogenation precooling method with high hydrogen utilization rate, characterized in that, This method is applied to a high hydrogen utilization rate rapid hydrogen refueling system as described in any one of claims 3 or 4. The method utilizes a booster pump (18), a first coolant tank (17), and a second coolant tank (16) to achieve rapid pre-cooling of hydrogen during the hydrogen refueling process.

8. The rapid hydrogen precooling method with high hydrogen utilization rate according to claim 7, characterized in that, The process of rapid pre-cooling of hydrogen during hydrogenation includes: after the start of refueling, the coolant in the first coolant tank (17) is pressurized by the booster pump (18) and flows into the heat exchanger (15). After the coolant exchanges heat with hydrogen at the heat exchanger (15), it flows into the second coolant tank (16) for recovery until the end of refueling.

9. The rapid hydrogenation precooling method with high hydrogen utilization rate according to claim 7, characterized in that, The speed of the booster pump (18) during the cooling process is adjusted according to the inlet temperature of the on-board hydrogen storage tank assembly (19).

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