Liquid hydrogen energy gradient utilization multi-source power generation system and power generation method

Abstract

The invention discloses a liquid hydrogen energy gradient utilization multi-source power generation system and method, and belongs to the field of aviation power generation. The problems that the overall energy efficiency of a hydrogen fuel cell power system is limited and the energy utilization rate of a gas turbine hydrogen fuel system is low are solved. According to the system, an outlet of a liquid hydrogen tank is sequentially communicated with an inlet of a liquid hydrogen pump and a cold end inlet of a liquid hydrogen-helium xenon heat exchanger, a cold end outlet is communicated with a fuel cell hydrogen inlet, and an unreacted hydrogen outlet is communicated with a combustion chamber hydrogen inlet; an outlet of the helium-xenon compressor communicates with a cold end inlet of the heat regenerator, a cold end outlet communicates with an inlet of the cooling channel, and an outlet communicates with an inlet of the helium-xenon turbine; an outlet of the helium-xenon turbine is communicated with a hot end inlet of the heat regenerator, a hot end outlet is communicated with a hot end inlet of the liquid hydrogen-helium-xenon heat exchanger, and a hot end outlet is communicated with an inlet of the helium-xenon gas compressor; a first outlet of the gas compressor communicates with the fuel cell air inlet, a second outlet communicates with the combustion chamber air inlet, and a combustion chamber outlet communicates with the turbine inlet. Mainly used in the energy field.

Description

Technical Field

[0001] This invention belongs to the field of aviation power generation, and in particular relates to a multi-source power generation system that utilizes liquid hydrogen energy in a cascade manner. Background Technology

[0002] With the development of the air transport industry, traditional fuel-powered aircraft, due to their high energy density, dominate long-distance, heavy-payload flight missions. However, this type of propulsion system has significant drawbacks: on the one hand, the combustion of hydrocarbon fuels produces large amounts of carbon dioxide (CO2) and nitrogen oxides (NOx). x Greenhouse gases and pollutants, such as fuel consumption, exacerbate global climate change and environmental pollution; on the other hand, the huge fuel consumption leads to a continuous increase in operating costs, making it difficult to meet the development requirements of green aviation.

[0003] To reduce carbon emissions from aviation, hydrogen energy, as a zero-carbon fuel, has received widespread attention. Current mainstream technological approaches focus on two main types of solutions: 1. Hydrogen fuel cell power system: It directly converts the chemical energy of hydrogen into electrical energy through electrochemical reaction, and only emits water vapor. However, its energy utilization has a bottleneck - liquid hydrogen storage temperature is as low as -253℃, and the huge amount of cold energy contained in the vaporization process (accounting for about 30% of the total energy of hydrogen) is usually wasted; at the same time, the high-grade waste heat generated in the operating temperature range of fuel cells (such as 600-1000℃ for solid oxide fuel cells) is not effectively recovered, resulting in limited overall system energy efficiency.

[0004] 2. Gas turbine hydrogen fuel system: Hydrogen is burned in the combustion chamber instead of traditional aviation fuel. Although it can achieve zero carbon emissions, it does not solve the problem of wasting liquid hydrogen cold energy, and a single power form is difficult to break through the upper limit of thermodynamic cycle efficiency.

[0005] Furthermore, the closed Brayton cycle is considered an ideal choice for aviation auxiliary power due to its compact size, lightweight design, and good environmental adaptability. However, in existing technologies, this cycle system mostly operates independently: its cold source relies on external cooling equipment, and its heat source requires independent combustion for heating, failing to achieve energy synergy with the fuel cell system, resulting in equipment redundancy and low energy utilization. Summary of the Invention

[0006] In view of this, the present invention aims to propose a multi-source power generation system and method for the cascade utilization of liquid hydrogen energy, in order to solve the problems of environmental pollution from hydrocarbon fuel combustion, limited overall energy efficiency of hydrogen fuel cell power systems, and low energy utilization rate of gas turbine hydrogen fuel systems.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: A liquid hydrogen energy cascade utilization multi-source power generation system, the system comprising: Liquid hydrogen tank, liquid hydrogen pump, liquid hydrogen-helium-xenon heat exchanger, fuel cell, helium-xenon compressor, generator, helium-xenon turbine, regenerator, compressor, combustion chamber, turbine and cooling passage; The outlet of the liquid hydrogen tank is connected to the inlet of the liquid hydrogen pump, the outlet of the liquid hydrogen pump is connected to the cold end inlet of the liquid hydrogen-helium-xenon heat exchanger, the cold end outlet of the liquid hydrogen-helium-xenon heat exchanger is connected to the hydrogen inlet of the fuel cell, and the unreacted hydrogen outlet of the fuel cell is connected to the hydrogen inlet of the combustion chamber. The outlet of the helium-xenon compressor is connected to the cold end inlet of the regenerator, the cold end outlet of the regenerator is connected to the inlet of the cooling channel, and the outlet of the cooling channel is connected to the inlet of the helium-xenon turbine. The outlet of the helium-xenon turbine is connected to the hot end inlet of the regenerator, the hot end outlet of the regenerator is connected to the hot end inlet of the liquid hydrogen-helium-xenon heat exchanger, and the hot end outlet of the liquid hydrogen-helium-xenon heat exchanger is connected to the inlet of the helium-xenon compressor, forming a closed Brayton cycle loop. The first outlet of the compressor is connected to the air inlet of the fuel cell, the second outlet of the compressor is connected to the air inlet of the combustion chamber, and the outlet of the combustion chamber is connected to the inlet of the turbine.

[0008] Furthermore, a preferred embodiment is proposed, wherein the working medium of the closed Brayton cycle loop is a helium-xenon mixture.

[0009] Furthermore, a preferred embodiment is proposed in which both the liquid hydrogen-helium-xenon heat exchanger and the regenerator are indirect heat exchangers.

[0010] Furthermore, a preferred embodiment is proposed, wherein the helium-xenon turbine and the turbine are axial-flow turbines or radial-flow turbines.

[0011] Furthermore, a preferred embodiment is proposed, wherein the fuel cell is a solid oxide fuel cell.

[0012] Furthermore, a preferred embodiment is proposed in which the helium-xenon compressor, the generator, and the helium-xenon turbine are arranged coaxially. During operation, the helium-xenon turbine drives the rotor shaft to rotate, thereby driving the generator to generate electricity and the helium-xenon compressor to pressurize the air.

[0013] Furthermore, a preferred embodiment is proposed in which the compressor and the turbine are arranged coaxially, and the compressor and the turbine are connected through the rotor shaft. During operation, the turbine drives the rotor shaft to rotate, thereby driving the compressor to work.

[0014] Furthermore, a preferred embodiment is proposed, wherein the liquid hydrogen cascade utilization comprises a three-stage gradient utilization: First stage: Liquid hydrogen cools the closed-loop working fluid through a liquid hydrogen-helium-xenon heat exchanger, reducing the inlet temperature of the helium-xenon compressor; Second stage: The vaporized hydrogen enters the fuel cell to generate electricity, and its waste heat heats the closed-loop working fluid through the cooling channel, increasing the inlet temperature of the closed-loop turbine. Third stage: Unreacted hydrogen from the fuel cell enters the combustion chamber and burns to drive the open-cycle turbine to do work.

[0015] Based on the same inventive concept, this invention also proposes a multi-source power generation method for the cascade utilization of liquid hydrogen energy. The method is implemented based on the multi-source power generation system described in any of the above claims, and includes: After being pressurized by the liquid hydrogen pump, the helium-xenon working fluid in the closed Brayton cycle is cooled by the liquid hydrogen-helium-xenon heat exchanger, which reduces the inlet temperature of the helium-xenon compressor and completes the first gradient energy utilization. The heat-absorbing vaporized hydrogen enters the solid oxide fuel cell to generate electricity. At the same time, the waste heat from the electrochemical process of the fuel cell is used to heat the high-pressure helium-xenon working fluid of the closed Brayton cycle through the cooling channel, thereby increasing the inlet temperature of the helium-xenon turbine and completing the second-gradient energy utilization. Unreacted hydrogen from the fuel cell is fed into the combustion chamber, where it mixes and burns with the gas split from the compressor, driving the turbine to do work and completing the third gradient of energy utilization. In a closed Brayton cycle, the exhaust gas from the helium-xenon turbine is preheated by a regenerator before returning to the liquid hydrogen-helium-xenon heat exchanger to complete the cycle.

[0016] Compared with the prior art, the beneficial effects of the present invention are: This invention proposes a multi-source power generation system for the cascade utilization of liquid hydrogen. By combining the cascade utilization of liquid hydrogen with various power generation technologies such as hydrogen fuel cells, gas turbines, and closed Brayton cycles, it can achieve highly efficient energy conversion and utilization. The cryogenic cold energy of liquid hydrogen is effectively recovered in multiple stages, avoiding a large amount of cold energy waste, thereby improving the overall energy efficiency of the system. Using hydrogen as fuel not only achieves zero carbon emissions but also effectively reduces the generation of pollutants such as nitrogen oxides, helping to reduce the negative environmental impact of air transport and meeting the requirements of green aviation.

[0017] By combining multiple technologies such as liquid hydrogen-helium-xenon heat exchangers, fuel cells, and gas turbines, this invention proposes a multi-source power generation system for the cascade utilization of liquid hydrogen energy, achieving synergistic energy operation across various stages. For example, the cold energy of liquid hydrogen is combined with the helium-xenon system through a heat exchanger, and the resulting high-grade waste heat can power the regenerator, thereby improving thermal energy utilization efficiency and overcoming the energy waste problem in traditional systems. The combination of the fuel cell with the hydrogen and air input system of the combustion chamber further enhances hydrogen utilization, and the unreacted hydrogen emissions are reused through a recovery system, further improving the energy efficiency of the hydrogen fuel cell. In this invention, the synergistic effect of the Brayton cycle with other energy conversion stages reduces energy waste and system redundancy. By optimizing liquid hydrogen cold energy recovery and multi-source energy synergy, the system proposed in this invention can significantly improve energy utilization efficiency, reduce energy consumption, and effectively control costs in aviation operations, demonstrating good economic viability.

[0018] This invention proposes a multi-source power generation system for the cascade utilization of liquid hydrogen energy. First, it utilizes cryogenic liquid hydrogen to cool a helium-xenon mixture, using the cryogenic liquid hydrogen as a cold source in a closed Brayton system to reduce the inlet temperature of the helium-xenon compressor, thus achieving the first gradient utilization of liquid hydrogen energy. Second, it fully utilizes the waste heat from the fuel cell to heat the helium-xenon mixture, increasing the inlet temperature of the helium-xenon turbine, thus achieving the second gradient utilization of liquid hydrogen energy. Third, unreacted hydrogen from the fuel cell enters the combustion chamber for combustion, and the resulting gas expands and performs work in the turbine, driving the compressor, thus achieving the third gradient utilization of liquid hydrogen energy.

[0019] This invention describes a multi-source power generation method for the cascaded utilization of liquid hydrogen energy, effectively leveraging the potential of liquid hydrogen through multiple gradient utilization methods. Liquid hydrogen undergoes multiple utilization stages, with energy being gradually released and efficiently converted at different stages, avoiding energy waste. For example, after being pressurized by the liquid hydrogen pump, it is first cooled through a liquid hydrogen-helium-xenon heat exchanger, and then undergoes energy conversion in multiple stages (such as fuel cells, combustion chambers, turbines, etc.), achieving multiple cascaded utilization of energy and maximizing the utilization efficiency of liquid hydrogen. Utilizing a closed Brayton cycle, helium-xenon, as the working fluid, possesses the characteristics of low temperature and low pressure, which can improve thermal efficiency and allows for multiple cycles within the system. This design helps reduce energy loss and improves the overall energy utilization rate of the system. Simultaneously, helium-xenon can continuously and effectively absorb and release heat in multi-stage heat exchange, further optimizing energy use.

[0020] In the power generation process of solid oxide fuel cells, not only is chemical energy effectively converted into electrical energy, but the high-pressure helium-xenon working fluid of the Brayton cycle is also heated by electrochemical waste heat, increasing the turbine inlet temperature and thus further improving energy utilization. Furthermore, unreacted hydrogen from the fuel cell mixes and combusts with the compressor's split gas, driving the turbine to perform work, further utilizing previously underutilized hydrogen and reducing energy waste. The method proposed in this invention achieves synergy through the combination of multiple power generation sources (liquid hydrogen, fuel cell, combustion chamber, etc.), enabling each component to complement each other. For example, liquid hydrogen provides a cooling source for the Brayton cycle, the fuel cell provides electrical and heat sources, and the combustion chamber generates power to drive the turbine through gas mixing and combustion. Attached Figure Description

[0021] The accompanying drawings, which constitute part of the present invention, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings: Figure 1 This is a schematic diagram of a multi-source power generation system for the cascade utilization of liquid hydrogen energy, as described in this invention.

[0022] In the picture: 1. Liquid hydrogen tank; 2. Liquid hydrogen pump; 3. Liquid hydrogen-helium-xenon heat exchanger; 4. Fuel cell; 5. Helium-xenon compressor; 6. Generator; 7. Helium-xenon turbine; 8. Regenerator; 9. Compressor; 10. Combustion chamber; 11. Turbine; 12. Cooling passage. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this embodiment clearer, the technical solutions of this 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 this invention. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0024] In the description of this invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., 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 limiting this invention.

[0025] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "communication" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0026] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0027] Implementation Method 1, see Figure 1 This embodiment describes a liquid hydrogen energy cascade utilization multi-source power generation system, the system comprising: Liquid hydrogen tank 1, liquid hydrogen pump 2, liquid hydrogen-helium-xenon heat exchanger 3, fuel cell 4, helium-xenon compressor 5, generator 6, helium-xenon turbine 7, regenerator 8, compressor 9, combustion chamber 10, turbine 11 and cooling channel 12; The outlet of the liquid hydrogen tank 1 is connected to the inlet of the liquid hydrogen pump 2, the outlet of the liquid hydrogen pump 2 is connected to the cold end inlet of the liquid hydrogen-helium-xenon heat exchanger 3, the cold end outlet of the liquid hydrogen-helium-xenon heat exchanger 3 is connected to the hydrogen inlet of the fuel cell 4, and the unreacted hydrogen outlet of the fuel cell 4 is connected to the hydrogen inlet of the combustion chamber 10. The outlet of the helium-xenon compressor 5 is connected to the cold end inlet of the regenerator 8, the cold end outlet of the regenerator 8 is connected to the inlet of the cooling channel 12, and the outlet of the cooling channel 12 is connected to the inlet of the helium-xenon turbine 7. The outlet of the helium-xenon turbine 7 is connected to the hot end inlet of the regenerator 8, the hot end outlet of the regenerator 8 is connected to the hot end inlet of the liquid hydrogen-helium-xenon heat exchanger 3, and the hot end outlet of the liquid hydrogen-helium-xenon heat exchanger 3 is connected to the inlet of the helium-xenon compressor 5, forming a closed Brayton cycle loop. The first outlet of the compressor 9 is connected to the air inlet of the fuel cell 4, the second outlet of the compressor 9 is connected to the air inlet of the combustion chamber 10, and the outlet of the combustion chamber 10 is connected to the inlet of the turbine 11.

[0028] This implementation method utilizes liquid hydrogen in a cascade manner, combining it with various power generation technologies such as hydrogen fuel cells, gas turbines, and closed Brayton cycles to achieve efficient energy conversion and utilization. The cryogenic cold energy of liquid hydrogen is effectively recovered in multiple stages, avoiding a significant waste of cold energy and thus improving the overall energy efficiency of the system.

[0029] Using hydrogen as fuel not only achieves zero carbon emissions but also effectively reduces the generation of pollutants such as nitrogen oxides, helping to reduce the negative environmental impact of air transport and meeting the needs of green aviation.

[0030] By combining multiple technologies such as liquid hydrogen-helium-xenon heat exchangers, fuel cells, and gas turbines, the system in this embodiment achieves synergistic energy operation across its various components. For example, the cold energy of liquid hydrogen is combined with the helium-xenon system through a heat exchanger, and the resulting high-grade waste heat can power the regenerator, thereby improving thermal efficiency and overcoming the energy waste problem in traditional systems. The fuel cell, combined with the hydrogen and air input system of the combustion chamber, results in higher hydrogen utilization, and the unreacted hydrogen emissions are reused through a recovery system, further improving the energy efficiency of the hydrogen fuel cell. In this embodiment, the synergistic effect of the Brayton cycle with other energy conversion stages reduces energy waste and system redundancy. By optimizing liquid hydrogen cold energy recovery and multi-source energy synergy, the system proposed in this embodiment can significantly improve energy utilization efficiency, reduce energy consumption, and effectively control costs in aviation operations, demonstrating good economic viability.

[0031] Implementation Method 2: This implementation method further defines the liquid hydrogen energy cascade utilization multi-source power generation system described in Implementation Method 1, characterized in that the working medium of the closed Brayton cycle loop is a helium-xenon mixture.

[0032] Implementation Method 3: This implementation method further defines the liquid hydrogen energy cascade utilization multi-source power generation system described in Implementation Method 1. The liquid hydrogen-helium-xenon heat exchanger 3 and the regenerator 8 are both indirect heat exchangers.

[0033] In this embodiment, a partitioned heat exchanger is used as the hydrogen-helium-xenon heat exchanger and regenerator. By using a partition to separate the two fluids, the risk of direct contact is avoided, effectively increasing the temperature gradient during the heat exchange process and thus improving the overall heat exchange efficiency. This is particularly important for regulating the temperature changes of liquid hydrogen and helium-xenon gas during the heat exchange process, which helps to recover and utilize thermal energy more efficiently.

[0034] Implementation Method 4: This implementation method further defines the liquid hydrogen energy cascade utilization multi-source power generation system described in Implementation Method 1, wherein the helium-xenon turbine 7 and turbine 11 are axial flow turbines or radial flow turbines.

[0035] In this embodiment, the axial and radial flow designs of the helium-xenon turbine and the turbine help improve the thermal energy conversion efficiency, especially in the cryogenic environment of liquid hydrogen, which helps to better extract effective energy from the heat source during the energy cascade utilization process.

[0036] Implementation Method 5: This implementation method further defines the liquid hydrogen energy cascade utilization multi-source power generation system described in Implementation Method 1, wherein the fuel cell 4 is a solid oxide fuel cell.

[0037] Implementation Method Six: This implementation method further defines the liquid hydrogen energy cascade utilization multi-source power generation system described in Implementation Method One. The helium-xenon compressor 5, the generator 6, and the helium-xenon turbine 7 are arranged coaxially. During operation, the helium-xenon turbine 7 drives the rotor shaft to rotate, thereby driving the generator 6 to generate electricity and the helium-xenon compressor 5 to pressurize.

[0038] In this embodiment, by arranging the helium-xenon compressor 5, generator 6, and helium-xenon turbine 7 coaxially, space can be effectively saved and the compactness of the equipment can be improved. This arrangement can reduce the internal volume of the system, which helps to reduce the overall size and weight of the equipment.

[0039] Furthermore, the coaxial arrangement design allows the helium-xenon turbine 7 to directly drive the generator 6 and the helium-xenon compressor 5 for pressurization, reducing transmission links. This direct drive structure reduces potential energy losses during power transmission, improves the overall system's energy utilization efficiency, and thus enhances the system's operating efficiency.

[0040] The configuration of a turbine-driven compressor and generator helps to maximize the recovery and utilization of every portion of energy during the cascade utilization of liquid hydrogen energy. The turbine drives the compressor to pressurize the gas while simultaneously driving the generator to produce electricity, improving overall energy efficiency and reducing energy waste.

[0041] Implementation Method Seven: This implementation method further defines the liquid hydrogen energy cascade utilization multi-source power generation system described in Implementation Method One. The compressor 9 and the turbine 11 are arranged coaxially, and the compressor 9 and the turbine 11 are connected through the rotor shaft. During operation, the turbine 11 drives the rotor shaft to rotate, thereby driving the compressor 9 to work.

[0042] In this embodiment, the turbine 11 and compressor 9 are coaxially arranged and connected via a rotor shaft, enabling direct energy transfer, effectively reducing energy loss and improving the overall system efficiency. Furthermore, the coaxial arrangement makes the system structure more compact, reducing space requirements and making it suitable for applications requiring high-density deployment, such as aerospace and mobile energy. Since the compressor and turbine are directly connected via the rotor shaft, power transmission does not require multi-stage transmissions or gear systems, significantly reducing frictional losses during mechanical transmission and minimizing energy loss. The turbine 11 drives the rotor shaft to rotate, thereby driving the compressor 9 to operate, ensuring the compressor receives stable driving force and further improving the stability and continuous output capability of the entire power generation system.

[0043] Implementation Method Eight: This implementation method further defines the liquid hydrogen energy cascade utilization multi-source power generation system described in Implementation Method One. The liquid hydrogen cascade utilization includes three-stage gradient utilization: First stage: Liquid hydrogen cools the closed-loop working fluid through liquid hydrogen-helium-xenon heat exchanger 3, reducing the inlet temperature of helium-xenon compressor 5; Second stage: The vaporized hydrogen enters the fuel cell 4 to generate electricity, and its waste heat heats the closed-loop working fluid through the cooling channel 12, increasing the inlet temperature of the closed-loop turbine 7. Third stage: Unreacted hydrogen from fuel cell 4 enters combustion chamber 10 for combustion, driving open-cycle turbine 11 to perform work.

[0044] This implementation utilizes a three-stage gradient approach to maximize the recovery and optimization of liquid hydrogen energy use. Each stage effectively converts and utilizes the energy of liquid hydrogen from different stages, thereby improving the overall system efficiency. The energy of liquid hydrogen is fully utilized at each stage, avoiding waste and improving overall energy conversion efficiency.

[0045] In the first stage, liquid hydrogen cools the closed-loop working fluid through a liquid hydrogen-helium-xenon heat exchanger, reducing the compressor inlet temperature. This design reduces the burden on the cooling system, avoids excessive energy consumption, and effectively improves the system's thermal efficiency and stability. Optimized working fluid temperature control avoids potential damage to the system caused by high temperatures, enhancing the long-term operational stability of the equipment.

[0046] In the second stage, the waste heat from the fuel cell heats the closed-loop working fluid through a cooling channel, increasing the inlet temperature of the closed-loop turbine and making full use of the waste heat resources in the system. This waste heat recovery technology not only improves system energy efficiency but also reduces dependence on external energy sources, lowering energy consumption and operating costs.

[0047] In the third stage, unreacted hydrogen from the fuel cell enters the combustion chamber for combustion, driving the open-cycle turbine to perform work, further improving the utilization rate of liquid hydrogen. This allows underutilized hydrogen to continue to be converted into useful work, avoiding energy waste and maximizing the energy output of hydrogen.

[0048] The three-stage cascade utilization model provides a flexible energy conversion scheme, which can adjust the energy flow of each stage according to different operating conditions, thereby improving the system's adaptability under various operating conditions. In addition, using liquid hydrogen as an energy source, combined with waste heat recovery and subsequent hydrogen combustion, ensures the system's sustainability and environmental friendliness, reducing dependence on traditional energy sources.

[0049] By combining various technologies such as liquid hydrogen-helium-xenon heat exchangers, fuel cells, and combustion chambers, the system's energy conversion and utilization have been optimized. Liquid hydrogen undergoes physical cooling, chemical energy conversion, and finally mechanical energy output, forming a closed-loop, highly efficient energy utilization system.

[0050] Implementation Method Nine: A multi-source power generation method for the cascade utilization of liquid hydrogen energy described in this implementation method is based on the multi-source power generation system described in any one of Implementation Methods One to Eight, and the method includes: After the liquid hydrogen pump pressurizes the gas, the liquid hydrogen-helium-xenon heat exchanger 3 cools the closed Brayton cycle helium-xenon working fluid, thereby reducing the inlet temperature of the helium-xenon compressor 5 and completing the first gradient energy utilization. The heat-absorbing vaporized hydrogen enters the solid oxide fuel cell 4 to generate electricity. At the same time, the waste heat from the electrochemical process of the fuel cell is used to heat the high-pressure helium-xenon working fluid of the closed Brayton cycle through the cooling channel 12, thereby increasing the inlet temperature of the helium-xenon turbine 7 and completing the second gradient energy utilization. Unreacted hydrogen from the fuel cell is introduced into the combustion chamber 10, where it mixes and burns with the gas split from the compressor 9, driving the turbine 11 to do work and completing the third gradient energy utilization. In the closed Brayton cycle, the exhaust gas from the helium-xenon turbine 7 is preheated by the regenerator 8 before returning to the liquid hydrogen-helium-xenon heat exchanger 3 to complete the cycle.

[0051] This embodiment describes a multi-source power generation method for the cascaded utilization of liquid hydrogen energy, effectively leveraging the potential of liquid hydrogen through multiple gradient utilization methods. Liquid hydrogen undergoes multiple utilization stages, with energy being gradually released and efficiently converted at different stages, avoiding energy waste. For example, after being pressurized by the liquid hydrogen pump, it is first cooled through a liquid hydrogen-helium-xenon heat exchanger, and then undergoes energy conversion in multiple stages (such as fuel cells, combustion chambers, turbines, etc.), achieving multiple cascaded utilization of energy and maximizing the utilization efficiency of liquid hydrogen. Utilizing a closed Brayton cycle, helium-xenon, as the working fluid, possesses the characteristics of low temperature and low pressure, which can improve thermal efficiency and allows for multiple cycles within the system. This design helps reduce energy loss and improves the overall energy utilization rate of the system. Simultaneously, helium-xenon can continuously and effectively absorb and release heat in multi-stage heat exchange, further optimizing energy use.

[0052] In the power generation process of solid oxide fuel cells, not only is chemical energy effectively converted into electrical energy, but the high-pressure helium-xenon working fluid of the Brayton cycle is also heated by electrochemical waste heat, increasing the turbine inlet temperature and thus further improving energy utilization. Furthermore, unreacted hydrogen from the fuel cell is mixed and burned with the compressor's split gas to drive the turbine, further utilizing previously underutilized hydrogen and reducing energy waste. The method proposed in this embodiment achieves synergy through the combination of multiple power generation sources (liquid hydrogen, fuel cell, combustion chamber, etc.), enabling each component to complement each other. For example, liquid hydrogen provides a cooling source for the Brayton cycle, the fuel cell provides electrical and heat sources, and the combustion chamber generates power to drive the turbine through gas mixing and combustion. This multi-source power generation design effectively reduces dependence on a single energy source and improves the overall stability and reliability of the multi-source power generation system.

[0053] This method uses liquid hydrogen as the primary energy source, reducing dependence on traditional fossil fuels and minimizing environmental pollution. Furthermore, the system maximizes energy conversion efficiency through multiple cascade utilization stages, reducing energy waste and further improving energy utilization.

[0054] The specific embodiments of the present invention disclosed above are merely illustrative of the invention. These embodiments do not exhaustively describe all details, nor do they limit the invention to the specific embodiments described. Many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention.

Claims

1. A multi-source power generation system for the cascade utilization of liquid hydrogen energy, characterized in that, The system includes: Liquid hydrogen tank (1), liquid hydrogen pump (2), liquid hydrogen-helium-xenon heat exchanger (3), fuel cell (4), helium-xenon compressor (5), generator (6), helium-xenon turbine (7), regenerator (8), compressor (9), combustion chamber (10), turbine (11) and cooling passage (12); The outlet of the liquid hydrogen tank (1) is connected to the inlet of the liquid hydrogen pump (2), the outlet of the liquid hydrogen pump (2) is connected to the cold end inlet of the liquid hydrogen-helium-xenon heat exchanger (3), the cold end outlet of the liquid hydrogen-helium-xenon heat exchanger (3) is connected to the hydrogen inlet of the fuel cell (4), and the unreacted hydrogen outlet of the fuel cell (4) is connected to the hydrogen inlet of the combustion chamber (10). The outlet of the helium-xenon compressor (5) is connected to the cold end inlet of the regenerator (8), the cold end outlet of the regenerator (8) is connected to the inlet of the cooling channel (12), and the outlet of the cooling channel (12) is connected to the inlet of the helium-xenon turbine (7). The outlet of the helium-xenon turbine (7) is connected to the hot end inlet of the regenerator (8), the hot end outlet of the regenerator (8) is connected to the hot end inlet of the liquid hydrogen-helium-xenon heat exchanger (3), and the hot end outlet of the liquid hydrogen-helium-xenon heat exchanger (3) is connected to the inlet of the helium-xenon compressor (5), forming a closed Brayton cycle loop. The first outlet of the compressor (9) is connected to the air inlet of the fuel cell (4), the second outlet of the compressor (9) is connected to the air inlet of the combustion chamber (10), and the outlet of the combustion chamber (10) is connected to the inlet of the turbine (11).

2. The liquid hydrogen energy cascade utilization multi-source power generation system according to claim 1, characterized in that, The working medium of the closed Brayton cycle is a helium-xenon mixture.

3. The liquid hydrogen energy cascade utilization multi-source power generation system according to claim 1, characterized in that, Both the liquid hydrogen-helium-xenon heat exchanger (3) and the regenerator (8) are indirect heat exchangers.

4. A multi-source power generation system for the cascade utilization of liquid hydrogen energy according to claim 1, characterized in that, The helium-xenon turbine (7) and the turbine (11) are axial flow turbines or radial flow turbines.

5. A multi-source power generation system for the cascade utilization of liquid hydrogen energy according to claim 1, characterized in that, The fuel cell (4) is a solid oxide fuel cell.

6. A multi-source power generation system for the cascade utilization of liquid hydrogen energy according to claim 1, characterized in that, The helium-xenon compressor (5), the generator (6), and the helium-xenon turbine (7) are arranged coaxially. When working, the helium-xenon turbine (7) drives the rotor shaft to rotate, thereby driving the generator (6) to generate electricity and the helium-xenon compressor (5) to pressurize.

7. A multi-source power generation system for the cascade utilization of liquid hydrogen energy according to claim 1, characterized in that, The compressor (9) and the turbine (11) are arranged coaxially, and the compressor (9) and the turbine (11) are connected through the rotor shaft. When working, the turbine (11) drives the rotor shaft to rotate, thereby driving the compressor (9) to work.

8. A multi-source power generation system for the cascade utilization of liquid hydrogen energy according to claim 1, characterized in that, The cascade utilization of liquid hydrogen includes three-stage gradient utilization: First stage: Liquid hydrogen cools the closed-loop working fluid through the liquid hydrogen-helium-xenon heat exchanger (3), reducing the inlet temperature of the helium-xenon compressor (5); Second stage: The vaporized hydrogen enters the fuel cell (4) to generate electricity, and its waste heat heats the closed-loop working fluid through the cooling channel (12) to increase the inlet temperature of the closed-loop turbine (7); Third stage: Fuel cell (4) Unreacted hydrogen enters the combustion chamber (10) and combustion drives the open-cycle turbine (11) to do work.

9. A method for multi-source power generation through the cascade utilization of liquid hydrogen energy, characterized in that, The method is implemented based on the multi-source power generation system according to any one of claims 1 to 8, and the method includes: After the liquid hydrogen pump pressurizes the gas, the helium-xenon working fluid of the closed Brayton cycle is cooled by the liquid hydrogen-helium-xenon heat exchanger (3), which reduces the inlet temperature of the helium-xenon compressor (5) and completes the first gradient energy utilization. The heat-absorbing vaporized hydrogen enters the solid oxide fuel cell (4) to generate electricity. At the same time, the waste heat from the electrochemical process of the fuel cell is used to heat the high-pressure helium-xenon working fluid of the closed Brayton cycle through the cooling channel (12), thereby increasing the inlet temperature of the helium-xenon turbine (7) and completing the second gradient energy utilization. Unreacted hydrogen from the fuel cell is introduced into the combustion chamber (10), where it mixes and burns with the gas diverted from the compressor (9), driving the turbine (11) to do work and completing the third gradient energy utilization. In the closed Brayton cycle, the exhaust gas from the helium-xenon turbine (7) is preheated by the regenerator (8) and then returned to the liquid hydrogen-helium-xenon heat exchanger (3) to complete the cycle.

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