Multi-combined supply system and method integrating Carnot battery energy storage and liquid hydrogen cold energy

Abstract

The invention discloses a multi-combined supply system and method integrating Carnot cell energy storage and liquid hydrogen cold energy. The multi-combined supply system comprises a vapor compression refrigeration cycle charging system, a Rankine cycle discharging system, a low-temperature energy storage system, a high-temperature energy storage system, a liquid hydrogen cold energy utilization system, a fuel cell waste heat utilization system and a liquid hydrogen pipeline. The charging system comprises a first compressor, a first condenser, a second compressor, a second condenser, a first throttle valve and a first evaporator which are sequentially communicated and circulated; the high-temperature heat storage tank and the low-temperature heat storage tank of the high-temperature energy storage system exchange heat with the discharge system through the second evaporator and the third evaporator; a high-temperature cold storage tank and a low-temperature cold storage tank of the low-temperature energy storage system exchange heat with the charging system and the discharging system through a first evaporator and a third condenser respectively; the liquid hydrogen cold energy utilization system achieves the liquid hydrogen gasification cold energy power generation process. The efficient comprehensive energy system is constructed by using liquid hydrogen cold energy and fuel cell waste heat.

Description

Technical Field

[0001] The present invention relates to the technical field of energy storage system and liquid hydrogen cooling energy utilization, and in particular to a multi-generation system and method integrating Carnot battery energy storage and liquid hydrogen cooling energy. Background Art

[0002] At present, due to the instability and intermittency of renewable energy, we need to seek efficient ways to store electricity to balance energy supply and demand. The application of energy storage systems can achieve peak load shifting and valley filling, solve the problem of instability of renewable energy generation, help reduce dependence on fossil energy, and ensure the safety and stability of the energy system. Energy storage systems play an important role in promoting energy transformation.

[0003] At present, pumped storage and compressed air energy storage are the methods that can be applied commercially on a large scale. Compared with these two systems, the Carnot battery energy storage system is not restricted by geographical conditions, has a lower initial cost, and can meet the requirements of large storage energy and high density under flexible application conditions. Therefore, it is crucial to the development of energy storage technology in my country.

[0004] For example, a Chinese patent document with publication number CN 115095402 A discloses a Carnot battery energy storage system and a method of use, wherein the Carnot battery energy storage system includes an energy storage working unit, the energy storage working unit includes a first passage for circulating an energy storage working medium, the first passage includes an evaporator, a compressor unit, a heat storage device and a pressure reducing device connected in sequence; an energy release working unit includes a second passage for circulating an energy release working medium, the second passage includes a preheater connected to one end of the heat storage device, and an expansion unit, an energy release heat regenerator, a condenser, a boosting device and a three-way valve connected in sequence to the other end of the heat storage device, the three-way valve is connected to the energy release heat regenerator through a first pipeline, and the energy release heat regenerator is connected to the heat storage device; the three-way valve is connected to the preheater through a second pipeline; wherein the evaporator and the preheater are arranged in series in the industrial waste heat medium flow channel. A Chinese patent document with publication number CN 113824139 A discloses a method and device for transforming a Carnot battery energy storage system in a thermal power plant. The method includes the following modes: charging mode: the electric energy output by the thermal power unit or renewable energy is stored in the energy storage system in the form of heat energy through the charging system; discharging mode: the discharging system converts the heat energy in the energy storage system into electric energy.

[0005] Finding ways to replace fossil energy is becoming increasingly important. As a clean energy carrier, hydrogen has important applications in industries such as industry, steel, chemical industry, transportation and power generation. The transportation and storage methods of hydrogen include high-pressure gas transportation, pipeline transportation and liquid storage transportation. Liquid hydrogen storage is one of the important ways to improve the efficiency of hydrogen storage and transportation. At present, the development of liquid hydrogen refueling stations around the world is rapid. However, liquid hydrogen storage requires extremely low temperatures. During its use, hydrogen needs to be gasified from -252.8℃ to 25℃. This process consumes a lot of energy, and this part of cold energy has not yet been fully utilized.

[0006] Currently, there are few studies that combine Carnot battery technology with liquid hydrogen cold energy utilization technology. Therefore, how to effectively utilize the cold energy in the liquid hydrogen gasification process and establish a safe, economical and stable energy storage system is an urgent problem that technicians in this field need to solve. Summary of the invention

[0007] The present invention provides a multi-generation system and method integrating Carnot battery energy storage and liquid hydrogen cooling energy, which can not only utilize the cooling energy of the liquid hydrogen gasification process, but also provide an economical, safe and efficient energy storage method.

[0008] The technical solution of the present invention is as follows: A multi-generation system integrating Carnot battery energy storage and liquid hydrogen cooling energy, including a charging system, a discharging system, a low-temperature energy storage system, a high-temperature energy storage system, a liquid hydrogen cooling energy utilization system, a fuel cell waste heat utilization system, and a liquid hydrogen pipeline; The charging system includes a first compressor, a first condenser, a second compressor, a second condenser, a first throttle valve, and a first evaporator which are connected and circulated in sequence; the charging system exchanges heat with the liquid hydrogen pipeline through the first condenser and the second condenser, and exchanges heat with the low-temperature energy storage system through the first evaporator; The discharge system includes a first working fluid pump, a second evaporator, a first expander, a third evaporator, a second expander, and a third condenser which are connected and circulated in sequence; the discharge system exchanges heat with the high-temperature energy storage system through the second evaporator and the third evaporator, and exchanges heat with the low-temperature energy storage system through the third condenser; The low-temperature energy storage system includes a high-temperature cold storage tank and a low-temperature cold storage tank; a cold storage passage is formed between the outlet of the high-temperature cold storage tank and the inlet of the low-temperature cold storage tank, and cold energy is absorbed through the first evaporator; a cold release passage is formed between the inlet of the high-temperature cold storage tank and the outlet of the low-temperature cold storage tank, and cold energy is released through the third condenser; The high-temperature energy storage system includes a high-temperature heat storage tank and a low-temperature heat storage tank; a heat release path is formed between the outlet of the high-temperature heat storage tank and the inlet of the low-temperature heat storage tank, and heat is released through the second evaporator and the third evaporator; a heat storage path is formed between the inlet of the high-temperature heat storage tank and the outlet of the low-temperature heat storage tank, and heat is absorbed through the fourth heat exchanger; Liquid hydrogen cold energy utilization system, including a power generation cycle system, utilizing cold energy of liquid hydrogen pipelines to generate electricity; The fuel cell waste heat utilization system absorbs the waste heat of the fuel cell reactor through a steam compression heat pump cycle to provide thermal energy for the discharge system.

[0009] In the charging system, the heat medium inlet side and outlet side of the first condenser are respectively connected to the first compressor outlet and the second compressor inlet, the heat medium inlet side and outlet side of the second condenser are respectively connected to the second compressor outlet and the first throttle valve inlet, the first throttle valve outlet is connected to the refrigerant inlet side of the first evaporator, and the refrigerant outlet side of the first evaporator is connected to the first compressor inlet.

[0010] In the discharge system, the refrigerant side inlet and outlet of the second evaporator are respectively connected to the first working fluid pump outlet and the first expander inlet, the refrigerant side inlet and outlet of the third evaporator are respectively connected to the first expander outlet and the second expander inlet, the second expander outlet is connected to the heat medium side inlet of the third condenser, and the heat medium outlet side of the third condenser is connected to the inlet side of the first working fluid pump.

[0011] The low-temperature energy storage system includes a high-temperature cold storage tank, a third working fluid pump, a low-temperature cold storage tank, a second mixer and a second diverter which are connected and circulated in sequence; the inlet side of the low-temperature cold storage tank is connected to the outlet of the heat medium side of the first evaporator, the outlet of the low-temperature cold storage tank is connected to the inlet of the second diverter, the inlet side of the second mixer is respectively connected to the outlet of the refrigerant side of the heat exchanger for heat exchange with the cold user and the outlet of the refrigerant side of the third condenser, the inlet side of the high-temperature cold storage tank is connected to the outlet of the second mixer, the outlet of the high-temperature cold storage tank out of the second diverter is divided into two paths and is respectively connected to the inlet side of the third working fluid pump, and the outlet side of the third working fluid pump is connected to the inlet side of the heat medium side of the first evaporator.

[0012] The high-temperature energy storage system includes a low-temperature heat storage tank, a second working fluid pump, a fourth heat exchanger, a high-temperature heat storage tank, a first mixer and a first diverter which are sequentially connected and circulated; the inlet side of the high-temperature heat storage tank is connected to the refrigerant outlet side of the fourth heat exchanger, the outlet side of the high-temperature heat storage tank is connected to the inlet side of the first diverter, the outlet of the first diverter is divided into two paths, one path is connected to the heat medium inlet side of the heat exchanger for heat exchange with the heat user, and the other path is sequentially connected to the heat medium side inlet of the third evaporator and the heat medium side outlet of the second evaporator, the inlet side of the first mixer is connected to the heat medium side outlet of the heat exchanger for heat exchange with the heat user and the heat medium side outlet of the second evaporator, the inlet side of the low-temperature heat storage tank is connected to the outlet of the first mixer, the outlet side of the low-temperature heat storage tank is connected to the inlet side of the second working fluid pump, and the outlet side of the second working fluid pump is connected to the refrigerant side inlet of the fourth heat exchanger.

[0013] The liquid hydrogen cold energy utilization system includes a Brayton cycle power generation system, a Rankine power generation cycle system, and an intermediate cooling cycle system which are arranged in sequence along the liquid hydrogen pipeline.

[0014] The Brayton cycle power generation system comprises a third compressor, a first seawater heat exchanger, a third expander, and a first heat exchanger which are connected in a cycle in sequence; heat is exchanged with seawater through the first seawater heat exchanger, and heat is exchanged with a liquid hydrogen pipeline through the first heat exchanger.

[0015] The Brayton cycle power generation system uses helium as the working fluid, and the power generation process is as follows: the helium is pressurized by the third compressor and enters the first seawater heat exchanger to exchange heat with seawater. After heating, it enters the third expander to generate electricity. The helium after expansion and power generation enters the first heat exchanger and the liquid hydrogen pipeline for heat exchange, and the liquid hydrogen is converted into gas. The cooled helium enters the third compressor again to complete the closed Brayton power generation cycle.

[0016] The Rankine cycle power generation system comprises a fourth working fluid pump, a second seawater heat exchanger, a fourth expander, and a second heat exchanger which are sequentially connected and circulated; heat is exchanged with seawater through the second seawater heat exchanger, and heat is exchanged with a liquid hydrogen pipeline through the second heat exchanger.

[0017] The Rankine cycle power generation system uses propane as the working fluid, and the power generation process is as follows: liquid propane is pressurized by the fourth working fluid pump and sent to the second seawater heat exchanger, where it is vaporized after heat exchange with seawater. The gaseous propane enters the fourth expander to generate electricity. The gaseous propane after expansion and power generation enters the second heat exchanger, where it is cooled into liquid propane after heat exchange with hydrogen. The liquid propane enters the fourth working fluid pump again to complete the closed Rankine power generation cycle.

[0018] The intermediate cold-carrying circulation system includes a third heat exchanger and a sixth heat exchanger in a connected circulation; the cold energy of the liquid hydrogen pipeline is absorbed by the third heat exchanger, and the cold energy is released in the sixth heat exchanger for cooling the data center room.

[0019] The intermediate cooling circulation system uses ethylene glycol aqueous solution as the working fluid. The cooling fluid absorbs the remaining cold energy of hydrogen in the third heat exchanger and releases the cold energy in the sixth heat exchanger to cool the data center room.

[0020] The fuel cell waste heat utilization system includes a fourth compressor, a second throttle valve, and a fifth heat exchanger which are connected in sequence; the passage between the second throttle valve outlet and the fourth compressor inlet absorbs the waste heat of the fuel cell reactor through the fifth heat exchanger, and the passage between the fourth compressor outlet and the second throttle valve inlet provides heat energy to the high-temperature energy storage system through the fourth heat exchanger.

[0021] The working process of the fuel cell waste heat utilization system is as follows: the temperature of the gaseous working medium increases after being pressurized by the fourth compressor, and it enters the fourth heat exchanger to be liquefied, releasing heat to the high-temperature energy storage system working medium. The liquid working medium enters the second throttle valve for throttling and cooling, and after the pressure is reduced, it enters the fifth heat exchanger, where it is heated and vaporized by the waste heat of the fuel cell reactor. The gaseous working medium enters the fourth compressor again to complete the steam compression heat pump cycle.

[0022] Preferably, the working fluid of the charging system is a mixture of argon and ethane, and the cycle is a vapor compression refrigeration cycle.

[0023] Preferably, the working fluid of the discharge system is a mixture of argon and ethane, and the cycle is a Rankine cycle.

[0024] Preferably, the heat storage medium of the high-temperature energy storage system is n-pentane; and the cold storage medium of the low-temperature energy storage system is propane.

[0025] The present invention also provides a multi-energy supply method based on the multi-energy supply system, and the operation strategy is as follows: During the off-peak period of electricity consumption, the charging system, liquid hydrogen cooling energy utilization system and fuel cell waste heat utilization system are operated to input the excess power of the power grid, the electric energy of the liquid hydrogen cooling energy utilization system and the fuel cell reactor into the compressor, and the electric energy is converted into cold energy and stored in the low-temperature energy storage system. The waste heat of the fuel cell reactor is upgraded by the steam compression heat pump and stored in the high-temperature energy storage system; During peak hours of electricity consumption, the discharge system is operated to convert the stored cold and heat energy into electrical energy for users; In the cooling season, the flow ratio of the low-temperature energy storage system diverter is adjusted according to user demand to supply part of the cooling capacity to cooling users; During the heating season, the flow ratio of the high-temperature energy storage system diverter is adjusted according to user demand to supply part of the heat to heat users.

[0026] Compared with the prior art, the present invention has the following beneficial effects: (1) In the present invention, the excess electric energy of the power grid, the electric energy generated by liquid hydrogen cold energy and the electric energy generated by fuel cells are converted into cold energy and stored during the charging process. During the discharging process, the stored cold energy is converted into electric energy again, thereby achieving effective conversion of electric energy and cold energy. The multi-generation system of the present invention can achieve peak load shaving and valley filling, reduce the load pressure of the power grid during peak periods, balance the load fluctuations of the power grid, and ensure the stable operation of the power system.

[0027] (2) While realizing the energy storage of Carnot batteries, the present invention utilizes the large amount of cold energy generated during the gasification of liquid hydrogen and the large amount of heat energy released by the end-user fuel cell of hydrogen while generating electrical energy, thereby reducing energy waste and avoiding environmental pollution.

[0028] (3) The present invention realizes the gasification of liquid hydrogen to meet the supply of hydrogen to downstream users. The cold energy in the process of liquid hydrogen gasification is used to generate electricity through a heat exchanger. The high, medium and low-grade cold energy in the process of liquid hydrogen gasification is utilized to avoid waste of cold energy and improve energy utilization efficiency.

[0029] (4) The high-temperature energy storage system and the low-temperature energy storage system of the present invention can adjust the supply according to the user's demand for cold and hot energy during the charging and discharging process, thereby constructing a comprehensive energy system of cold-heat-electricity cogeneration. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 A schematic diagram of the structure of a multi-generation system integrating Carnot battery energy storage and liquid hydrogen cooling energy provided by an embodiment of the present invention; Explanation of reference numerals: 1. first compressor; 2. first condenser; 3. second compressor; 4. second condenser; 5. first throttle valve; 6. first evaporator; 7. first working fluid pump; 8. second evaporator; 9. first expander; 10. third evaporator; 11. second expander; 12. third condenser; 13. first mixer; 14. low-temperature heat storage tank; 15. second working fluid pump; 16. fourth heat exchanger; 17. high-temperature heat storage tank; 18. first diverter; 19. heat user heat exchanger; 20. second throttle valve; 21. fifth heat exchanger 22. the fourth compressor; 23. the fifth working fluid pump; 24. the first heat exchanger; 25. the second heat exchanger; 26. the third heat exchanger; 27. the heater; 28. the third compressor; 29. ​​the first seawater heat exchanger; 30. the third expander; 31. the fourth working fluid pump; 32. the second seawater heat exchanger; 33. the fourth expander; 34. the sixth heat exchanger; 35. the high-temperature cold storage tank; 36. the third working fluid pump; 37. the low-temperature cold storage tank; 38. the second diverter; 39. the cold user heat exchanger; 40. the second mixer; 41. the fuel cell reactor. DETAILED DESCRIPTION

[0031] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] The purpose of the present invention is to provide a multi-generation system and method integrating Carnot battery energy storage and liquid hydrogen cooling energy, which can not only realize efficient, stable, economical and safe energy storage, but also utilize the cooling energy in the process of liquid hydrogen gasification, effectively reducing energy waste.

[0033] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0034] refer to Figure 1 As shown, this embodiment provides a multi-generation system integrating Carnot battery energy storage and liquid hydrogen cooling energy, including: a charging process, a discharging process, a high-temperature energy storage system, a low-temperature energy storage system, a liquid hydrogen cooling energy utilization system, and a fuel cell waste heat utilization system.

[0035] During specific use, the charging process includes a first compressor 1, a first condenser 2 for heat exchange with liquid hydrogen cold energy, a second compressor 3, a second condenser 4 for heat exchange with liquid hydrogen cold energy, a first throttle valve 5, and a first evaporator 6 for heat exchange with the cold storage side; the heat medium inlet side and outlet side of the first condenser 2 are respectively connected to the outlet of the first compressor 1 and the inlet of the second compressor 3, the heat medium inlet side and outlet side of the second condenser 4 are respectively connected to the outlet of the second compressor 3 and the inlet of the first throttle valve 5, so as to utilize the cold energy in the gasification process of liquid hydrogen to exchange heat with the working fluid, the outlet of the first throttle valve 5 is connected to the refrigerant inlet side of the first evaporator 6, so as to exchange heat between the cold energy of the liquid working fluid in the charging process and the working fluid in the low-temperature energy storage process, and the refrigerant outlet side of the first evaporator 6 is connected to the inlet of the first compressor 1.

[0036] In this embodiment, specifically, when the charging process is running, the electric energy at low load of the power grid, the electric energy generated by the cold energy power generation during the liquid hydrogen gasification process, and the electric energy generated by the fuel cell power generation drive the first compressor 1 and the second compressor 3. The first compressor 1 compresses the working fluid, so that the temperature and pressure of the working fluid increase, and the high-temperature and high-pressure gaseous working fluid enters the first condenser 2 and the liquid hydrogen gasification pipeline for heat exchange. After the temperature is reduced, it enters the second compressor 3, and the high-temperature and high-pressure gaseous working fluid enters the second condenser 4 and the liquid hydrogen gasification pipeline for heat exchange. The cold energy liquefies the gaseous working fluid, and the liquid working fluid enters the first throttle valve 5 for further throttling and cooling, increasing the supercooling of the working fluid, and the low-temperature and low-pressure liquid working fluid enters the first evaporator 6 and the working fluid in the low-temperature energy storage process for heat exchange, transferring the cold to the low-temperature energy storage working fluid. After the working fluid is vaporized, it enters the first compressor 1 again to complete the steam compression refrigeration cycle of the charging process.

[0037] In this embodiment, specifically, the discharge process includes a first working fluid pump 7, a first expansion machine 9, a second expansion machine 11, a third condenser 12 for exchanging heat with the cold storage side, a second evaporator 8 and a third evaporator 10 for exchanging heat with the heat storage side; the refrigerant side inlet and outlet of the second evaporator 8 are respectively connected to the outlet of the first working fluid pump 7 and the inlet of the first expansion machine 9, the refrigerant side inlet and outlet of the third evaporator 10 are respectively connected to the outlet of the first expansion machine 9 and the inlet of the second expansion machine 11, the outlet of the second expansion machine 11 is connected to the heat medium side inlet of the third condenser 12, and the heat medium outlet side of the third condenser 12 is connected to the inlet side of the first working fluid pump 7.

[0038] In this embodiment, specifically, when the discharge process is running, the gaseous working fluid of the discharge process is cooled and liquefied by the low-temperature energy storage working fluid through the third condenser 12, the liquid working fluid is pressurized by the first working fluid pump 7 and enters the second evaporator 8, and is heated and vaporized by the working fluid of the high-temperature energy storage process in the second evaporator 8, the gaseous working fluid enters the first expander 9 to generate electricity, the low-temperature working fluid coming out of the first expander 9 enters the third evaporator 10, and enters the second expander 11 to generate electricity after being heated by the third evaporator 10, converting cold energy into electrical energy, and the low-temperature and low-pressure working fluid after power generation enters the third condenser 12, completing the Rankine cycle of the discharge process.

[0039] In this embodiment, specifically, the high-temperature energy storage system includes a high-temperature heat storage tank 17, a low-temperature heat storage tank 14, a second working fluid pump 15, a first mixer 13 and a first diverter 18. The inlet side of the high-temperature heat storage tank 17 is connected to the refrigerant outlet side of the fourth heat exchanger 16 on the heat release side of the steam compression heat pump, the outlet of the high-temperature heat storage tank 17 is connected to the inlet of the first diverter 18, the outlet of the first diverter 18 is connected to the heat medium side inlet of the heat user heat exchanger 19 and the heat medium side inlet of the third evaporator 10 in the discharge process, the inlet side of the first mixer 13 is connected to the heat medium side outlet of the heat user heat exchanger 19 and the heat medium side outlet of the second evaporator 8 in the discharge process, the inlet side and the outlet side of the low-temperature heat storage tank 14 are respectively connected to the outlet of the first mixer 13 and the inlet side of the second working fluid pump 15, and the outlet side of the second working fluid pump 15 is connected to the refrigerant side inlet of the fourth heat exchanger 16 on the heat release side of the steam compression heat pump.

[0040] In this embodiment, specifically, the high-temperature heat storage medium in the high-temperature heat storage tank 17 enters the first diverter 18, and the flow rate ratio to the heat user heat exchanger 19 and the third evaporator 10 in the discharge process can be adjusted according to the energy demand of the heat user to release heat and meet the heating demand of the heat user. After the heat is released, it enters the first mixer 13 and flows to the low-temperature heat storage tank 14. The heat storage medium in the low-temperature heat storage tank 14 is pressurized by the second working medium pump 15 and enters the fourth heat exchanger 16, absorbs the waste heat of the fuel cell and improves the quality of the heat through the steam compression heat pump, and then enters the high-temperature heat storage tank 17 to store heat.

[0041] In this embodiment, specifically, the low-temperature energy storage system includes a high-temperature cold storage tank 35, a low-temperature cold storage tank 37, a third working fluid pump 36, a second mixer 40 and a second diverter 38. The inlet side and the outlet side of the low-temperature cold storage tank 37 are respectively connected to the heat medium side outlet of the first evaporator 6 in the charging process and the inlet of the second diverter 38, the outlet of the second diverter 38 is connected to the refrigerant side inlet of the cold user heat exchanger 39 and the refrigerant side inlet of the third condenser 12 in the discharging process, the inlet side of the second mixer 40 is connected to the refrigerant side outlet of the cold user heat exchanger 39 and the refrigerant side outlet of the third condenser 12 in the discharging process, the inlet side and the outlet side of the high-temperature cold storage tank 35 are respectively connected to the outlet of the second mixer 40 and the inlet side of the third working fluid pump 36, and the outlet side of the third working fluid pump 36 is connected to the heat medium side inlet side of the first evaporator 6 in the charging process.

[0042] In this embodiment, specifically, the low-temperature cold storage medium in the low-temperature cold storage tank 37 enters the second diverter 38, and the flow rate ratio to the heat exchanger for heat exchange with the cold user and the third condenser 12 in the discharge process can be adjusted according to the energy demand of the cold user to release the cold, so as to meet the cold supply demand of the cold user. After the cold is released, it enters the second mixer 40 and flows to the high-temperature cold storage tank 35. The cold storage medium in the high-temperature cold storage tank 35 is pressurized by the third working medium pump 36 and enters the first evaporator 6 in the charging process to absorb the cold from the charging process, and then enters the low-temperature cold storage tank 37 for cold storage.

[0043] In this embodiment, specifically, the liquid hydrogen cold energy utilization system includes a Brayton power generation cycle, a Rankine power generation cycle, and a data center cooling cycle. The first condenser 2 and the second condenser 4 of the charging process exchange heat with the liquid hydrogen pipeline to provide cold energy for the charging process; the liquid hydrogen cold energy utilization system includes a Brayton cycle power generation process using helium as the working fluid as follows: the helium is pressurized by the third compressor 28 and enters the first seawater heat exchanger 29 to exchange heat with seawater. After heating, it enters the third expander 30 to generate electricity. The helium after expansion and power generation enters the first heat exchanger 24 to exchange heat with liquid hydrogen, and the liquid hydrogen is gasified into a gaseous state. The cooled helium enters the third compressor 28 again to complete the closed Brayton power generation cycle. The Rankine cycle power generation process using propane as the working fluid is as follows: liquid propane is pressurized by the fourth working fluid pump 31 and sent to the second seawater heat exchanger 32, where it is vaporized after heat exchange with seawater, and the gaseous propane enters the fourth expander 33 to generate electricity. The gaseous propane after expansion and power generation enters the second heat exchanger 25, where it is cooled to liquid propane after heat exchange with hydrogen, and the liquid propane enters the fourth working fluid pump 31 again to complete the closed Rankine power generation cycle; the data center cooling cycle using ethylene glycol aqueous solution as the working fluid is as follows: the ethylene glycol aqueous solution passes through the third heat exchanger 26, exchanges heat with hydrogen, and after cooling, enters the sixth heat exchanger 34 to release cold energy to the data center computer room. The heated ethylene glycol aqueous solution enters the third heat exchanger again to complete the data center cooling cycle.

[0044] In this embodiment, specifically, the function of the heater 27 is to adjust the temperature of the hydrogen. The outlet hydrogen temperature can be adjusted according to different terminal requirements to achieve flexible gas supply.

[0045] In this embodiment, specifically, the fuel cell waste heat utilization system includes a fuel cell reactor 41, and a steam compression heat pump cycle provides thermal energy for the discharge process. The gaseous working medium is pressurized by the fourth compressor 22, and its temperature rises, and it enters the fourth heat exchanger 16 to liquefy, releasing heat to the high-temperature energy storage system working medium. The liquid working medium enters the second throttle valve 20 for throttling and cooling, and after the pressure is reduced, it enters the fifth heat exchanger 21, and is heated and vaporized by the waste heat of the fuel cell. The gaseous working medium enters the fourth compressor 22 again, completing the steam compression heat pump cycle, and the quality of the waste heat of the fuel cell is improved.

[0046] In this embodiment, specifically, the working fluid of the charging process is a mixture of argon and ethane, and the cycle is a vapor compression refrigeration cycle.

[0047] In this embodiment, specifically, the working fluid of the discharge process is a mixture of argon and ethane, and the cycle is a Rankine cycle.

[0048] In this embodiment, specifically, the heat storage medium of the high-temperature energy storage system is n-pentane, and the cold storage medium of the low-temperature energy storage system is propane.

[0049] In this embodiment, specifically, the multi-generation method integrating Carnot battery energy storage and liquid hydrogen cooling energy includes charging, discharging, heating, and cooling. The specific operation strategy is as follows: During the off-peak period of electricity consumption, the charging process, liquid hydrogen cold energy utilization system and fuel cell waste heat utilization system are operated. During the charging process, excess power from the power grid, liquid hydrogen cold energy generation and fuel cell power generation are input into the compressor, and the electric energy is converted into cold energy and stored in the low-temperature energy storage system. The waste heat of the fuel cell is upgraded by the steam compression heat pump and stored in the high-temperature energy storage system. During peak hours of electricity consumption, the discharge process is run, and the stored cold and heat energy is converted into electrical energy for users; In the cooling season, the flow ratio of the low-temperature energy storage system diverter is adjusted according to user demand to supply part of the cooling capacity to cooling users; During the heating season, the flow ratio of the high-temperature energy storage system diverter is adjusted according to user demand to supply part of the heat to heat users.

[0050] The embodiments described above provide a detailed description of the technical solutions and beneficial effects of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, supplements and equivalent substitutions made within the scope of the principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A multi-generation system integrating Carnot battery energy storage and liquid hydrogen cooling energy, characterized in that: Including charging system, discharging system, low-temperature energy storage system, high-temperature energy storage system, liquid hydrogen cold energy utilization system, fuel cell waste heat utilization system, and liquid hydrogen pipeline; The charging system includes a first compressor, a first condenser, a second compressor, a second condenser, a first throttle valve, and a first evaporator which are connected and circulated in sequence; the charging system exchanges heat with the liquid hydrogen pipeline through the first condenser and the second condenser, and exchanges heat with the low-temperature energy storage system through the first evaporator; The discharge system includes a first working fluid pump, a second evaporator, a first expander, a third evaporator, a second expander, and a third condenser which are connected and circulated in sequence; the discharge system exchanges heat with the high-temperature energy storage system through the second evaporator and the third evaporator, and exchanges heat with the low-temperature energy storage system through the third condenser; The low-temperature energy storage system includes a high-temperature cold storage tank and a low-temperature cold storage tank; a cold storage passage is formed between the outlet of the high-temperature cold storage tank and the inlet of the low-temperature cold storage tank, and cold energy is absorbed through the first evaporator; a cold release passage is formed between the inlet of the high-temperature cold storage tank and the outlet of the low-temperature cold storage tank, and cold energy is released through the third condenser; The high-temperature energy storage system includes a high-temperature heat storage tank and a low-temperature heat storage tank; a heat release path is formed between the outlet of the high-temperature heat storage tank and the inlet of the low-temperature heat storage tank, and heat is released through the second evaporator and the third evaporator; a heat storage path is formed between the inlet of the high-temperature heat storage tank and the outlet of the low-temperature heat storage tank, and heat is absorbed through the fourth heat exchanger; Liquid hydrogen cold energy utilization system, including a power generation cycle system, utilizing cold energy of liquid hydrogen pipelines to generate electricity; The fuel cell waste heat utilization system absorbs the waste heat of the fuel cell reactor through a steam compression heat pump cycle to provide thermal energy for the discharge system.

2. The multi-generation system integrating Carnot battery energy storage and liquid hydrogen cooling energy according to claim 1 is characterized in that: In the charging system, the heat medium inlet side and outlet side of the first condenser are respectively connected to the first compressor outlet and the second compressor inlet, the heat medium inlet side and outlet side of the second condenser are respectively connected to the second compressor outlet and the first throttle valve inlet, the first throttle valve outlet is connected to the refrigerant inlet side of the first evaporator, and the refrigerant outlet side of the first evaporator is connected to the first compressor inlet.

3. The multi-generation system integrating Carnot battery energy storage and liquid hydrogen cooling energy according to claim 1 is characterized in that: In the discharge system, the refrigerant side inlet and outlet of the second evaporator are respectively connected to the first working fluid pump outlet and the first expander inlet, the refrigerant side inlet and outlet of the third evaporator are respectively connected to the first expander outlet and the second expander inlet, the second expander outlet is connected to the heat medium side inlet of the third condenser, and the heat medium outlet side of the third condenser is connected to the inlet side of the first working fluid pump.

4. The multi-generation system integrating Carnot battery energy storage and liquid hydrogen cooling energy according to claim 1 is characterized in that: The low-temperature energy storage system includes a high-temperature cold storage tank, a third working fluid pump, a low-temperature cold storage tank, a second mixer and a second diverter which are connected and circulated in sequence; the inlet side of the low-temperature cold storage tank is connected to the outlet of the heat medium side of the first evaporator, the outlet of the low-temperature cold storage tank is connected to the inlet of the second diverter, the inlet side of the second mixer is respectively connected to the outlet of the refrigerant side of the heat exchanger for heat exchange with the cold user and the outlet of the refrigerant side of the third condenser, the inlet side of the high-temperature cold storage tank is connected to the outlet of the second mixer, the outlet of the high-temperature cold storage tank out of the second diverter is divided into two paths and is respectively connected to the inlet side of the third working fluid pump, and the outlet side of the third working fluid pump is connected to the inlet side of the heat medium side of the first evaporator.

5. The multi-generation system integrating Carnot battery energy storage and liquid hydrogen cooling energy according to claim 1 is characterized in that: The high-temperature energy storage system includes a low-temperature heat storage tank, a second working fluid pump, a fourth heat exchanger, a high-temperature heat storage tank, a first mixer and a first diverter which are sequentially connected and circulated; the inlet side of the high-temperature heat storage tank is connected to the refrigerant outlet side of the fourth heat exchanger, the outlet side of the high-temperature heat storage tank is connected to the inlet side of the first diverter, the outlet of the first diverter is divided into two paths, one path is connected to the heat medium inlet side of the heat exchanger for heat exchange with the heat user, and the other path is sequentially connected to the heat medium side inlet of the third evaporator and the heat medium side outlet of the second evaporator, the inlet side of the first mixer is connected to the heat medium side outlet of the heat exchanger for heat exchange with the heat user and the heat medium side outlet of the second evaporator, the inlet side of the low-temperature heat storage tank is connected to the outlet of the first mixer, the outlet side of the low-temperature heat storage tank is connected to the inlet side of the second working fluid pump, and the outlet side of the second working fluid pump is connected to the refrigerant side inlet of the fourth heat exchanger.

6. The multi-generation system integrating Carnot battery energy storage and liquid hydrogen cooling energy according to claim 1 is characterized in that: The liquid hydrogen cold energy utilization system includes a Brayton cycle power generation system, a Rankine power generation cycle system, and an intermediate cold-carrying cycle system arranged in sequence along the liquid hydrogen pipeline; the Brayton cycle power generation system includes a third compressor, a first seawater heat exchanger, a third expander, and a first heat exchanger that are sequentially connected and circulated; heat is exchanged with seawater through the first seawater heat exchanger, and heat is exchanged with the liquid hydrogen pipeline through the first heat exchanger; the Rankine cycle power generation system includes a fourth working fluid pump, a second seawater heat exchanger, a fourth expander, and a second heat exchanger that are sequentially connected and circulated; heat is exchanged with seawater through the second seawater heat exchanger, and heat is exchanged with the liquid hydrogen pipeline through the second heat exchanger; the intermediate cold-carrying cycle system includes a third heat exchanger and a sixth heat exchanger that are connected and circulated; cold energy of the liquid hydrogen pipeline is absorbed through the third heat exchanger, and cold energy is released in the sixth heat exchanger.

7. The multi-generation system integrating Carnot battery energy storage and liquid hydrogen cooling energy according to claim 1 is characterized in that: The fuel cell waste heat utilization system includes a fourth compressor, a second throttle valve, and a fifth heat exchanger which are connected in sequence; the passage between the second throttle valve outlet and the fourth compressor inlet absorbs the waste heat of the fuel cell reactor through the fifth heat exchanger, and the passage between the fourth compressor outlet and the second throttle valve inlet provides heat energy to the high-temperature energy storage system through the fourth heat exchanger.

8. The multi-generation system integrating Carnot battery energy storage and liquid hydrogen cooling energy according to claim 1 is characterized in that: The working fluid of the charging system is a mixture of argon and ethane, and the cycle is a vapor compression refrigeration cycle; the working fluid of the discharging system is a mixture of argon and ethane, and the cycle is a Rankine cycle.

9. The multi-generation system integrating Carnot battery energy storage and liquid hydrogen cooling energy according to claim 1, characterized in that: The heat storage medium of the high-temperature energy storage system is n-pentane; the cold storage medium of the low-temperature energy storage system is propane.

10. A combined power generation method based on the combined power generation system according to any one of claims 1 to 9, characterized in that: The operation strategy is as follows: During the off-peak period of electricity consumption, the charging system, liquid hydrogen cooling energy utilization system and fuel cell waste heat utilization system are operated to input the excess power of the power grid, the electric energy of the liquid hydrogen cooling energy utilization system and the fuel cell reactor into the compressor, and the electric energy is converted into cold energy and stored in the low-temperature energy storage system. The waste heat of the fuel cell reactor is upgraded by the steam compression heat pump and stored in the high-temperature energy storage system; During peak hours of electricity consumption, the discharge system is operated to convert the stored cold and heat energy into electrical energy for users; In the cooling season, the flow ratio of the low-temperature energy storage system diverter is adjusted according to user demand to supply part of the cooling capacity to cooling users; During the heating season, the flow ratio of the high-temperature energy storage system diverter is adjusted according to user demand to supply part of the heat to heat users.

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