A multi-supply system and method integrating carnot cell energy storage and liquid hydrogen cold energy

Abstract

The application discloses a multi-supply system and method integrating Carnot cell energy storage and liquid hydrogen cold energy, comprising 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 throttling valve and a first evaporator which are sequentially connected in a circulation mode; the high-temperature energy storage system is in heat exchange with the discharging system through a second evaporator and a third evaporator; the low-temperature energy storage system is in heat exchange with the charging and discharging systems through a first evaporator and a third condenser respectively; and the liquid hydrogen cold energy utilization system realizes a liquid hydrogen gasification cold energy power generation process. The application utilizes liquid hydrogen cold energy and fuel cell waste heat to construct a high-efficiency comprehensive energy system.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of energy storage systems and liquid hydrogen cold energy utilization, and in particular to a multi-supply system and method integrating Carnot battery energy storage and liquid hydrogen cold energy. BACKGROUND

[0002] Currently, renewable energy needs to seek efficient electric energy storage methods due to its instability and intermittency to balance energy supply and demand. The application of energy storage systems can achieve peak load shifting of electric power, 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. In terms of promoting energy transformation, energy storage systems play an important role.

[0003] Currently, pumped storage and compressed air energy storage are the ways that can be used on a large scale. Compared with these two systems, the Carnot battery energy storage system does not need to be limited by geographical conditions, has a lower initial cost, and can meet the requirements of large energy storage, high density, and flexible application. Therefore, it is crucial for the development of China's energy storage technology.

[0004] For example, the Chinese patent document with publication number CN 115095402 A discloses a Carnot battery energy storage system and use method. The Carnot battery energy storage system includes an energy storage working unit, which includes a first passage for circulating energy storage working medium, and the first passage includes, in sequence, an evaporator, a compressor set, a heat storage device, and a pressure reducing device. The energy release working unit includes a second passage for circulating energy release working medium, and the second passage includes a preheater connected to one end of the heat storage device, and an expansion machine set, an energy release regenerator, a condenser, a pressure increasing 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 regenerator through a first pipeline, and the energy release regenerator is connected to the heat storage device. The three-way valve is connected to the preheater through a second pipeline. The evaporator and the preheater are arranged in series in an industrial waste heat medium flow channel. The Chinese patent document with publication number CN 113824139 A discloses a Carnot battery energy storage modification method and device for 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 heat energy in the energy storage system is converted into electric energy by the discharging system.

[0005] It is increasingly important to find alternative fossil energy sources. Hydrogen, as a clean energy carrier, has important applications in industries, steel, chemical industry, transportation and power generation. Hydrogen transportation and storage methods include high-pressure gaseous transportation, pipeline transportation and liquid storage transportation. Liquid hydrogen storage is one of the important ways to improve hydrogen storage and transportation efficiency. At present, the global liquid hydrogen refueling station is developing rapidly. However, liquid hydrogen storage requires extremely low temperature, and during its use, hydrogen needs to be gasified from-252.8 DEG C to 25 DEG C, which consumes a lot of energy, and the cold energy has not been fully utilized.

[0006] Currently, few studies combine Carnot battery technology and 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 a problem to be solved by technical personnel in the field. SUMMARY

[0007] The application provides a multi-combined heat and power system and method integrating Carnot battery energy storage and liquid hydrogen cold energy, which not only utilizes the cold energy in the liquid hydrogen gasification process, but also provides an economical, safe and efficient energy storage method.

[0008] The technical scheme of the application is as follows:

[0009] A multi-combined heat and power system integrating Carnot battery energy storage and liquid hydrogen cold energy, comprising a charging system, a 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.

[0010] The charging system comprises a first compressor, a first condenser, a second compressor, a second condenser, a first throttle valve and a first evaporator connected in sequence and circulating; 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;

[0011] The discharging system comprises a first working fluid pump, a second evaporator, a first expander, a third evaporator, a second expander and a third condenser connected in sequence and circulating; the discharging 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;

[0012] The low-temperature energy storage system comprises 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;

[0013] The high-temperature energy storage system comprises a high-temperature heat storage tank and a low-temperature heat storage tank; a heat release passage 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 passage 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;

[0014] The liquid hydrogen cold energy utilization system comprises a power generation cycle system, and utilizes the cold energy of a liquid hydrogen pipeline to generate power.

[0015] The fuel cell waste heat utilization system absorbs the waste heat of a fuel cell reactor through a steam compression heat pump cycle to provide heat energy for a discharge system.

[0016] In the charging system, the heat medium inlet side and the outlet side of the first condenser are connected to the outlet of the first compressor and the inlet of the second compressor respectively, the heat medium inlet side and the outlet side of the second condenser are connected to the outlet of the second compressor and the inlet of the first throttling valve respectively, the outlet of the first throttling valve is connected to the refrigerant inlet side of the first evaporator, and the refrigerant outlet side of the first evaporator is connected to the inlet of the first compressor.

[0017] In the discharge system, the refrigerant side inlet and the outlet of the second evaporator are connected to the outlet of the first working medium pump and the inlet of the first expander respectively, the refrigerant side inlet and the outlet of the third evaporator are connected to the outlet of the first expander and the inlet of the second expander respectively, the outlet of the second expander 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 medium pump.

[0018] The low-temperature energy storage system comprises a high-temperature cold storage tank, a third working medium pump, a low-temperature cold storage tank, a second mixer and a second flow divider connected in sequence; the inlet side of the low-temperature cold storage tank is connected to the heat medium side outlet of the first evaporator, the outlet of the low-temperature cold storage tank is connected to the inlet of the second flow divider, the inlet side of the second mixer is connected to the refrigerant side outlet of a heat exchanger for heat exchange with a cold user and the refrigerant side outlet of the third condenser respectively, the outlet of the second mixer is connected to the inlet side of the high-temperature cold storage tank, the outlet of the high-temperature cold storage tank is connected to the second flow divider, and the refrigerant side inlet of the heat exchanger for heat exchange with the cold user and the refrigerant side inlet of the third condenser are connected to the outlet of the second flow divider respectively, the inlet side of the high-temperature cold storage tank is connected to the inlet side of the third working medium pump, and the outlet side of the third working medium pump is connected to the heat medium side inlet side of the first evaporator.

[0019] The high-temperature energy storage system comprises a low-temperature heat storage tank, a second working medium pump, a fourth heat exchanger, a high-temperature heat storage tank, a first mixer and a first flow divider which are sequentially connected in circulation; the high-temperature heat storage tank inlet side is connected with the fourth heat exchanger cold medium outlet side, the high-temperature heat storage tank outlet side is connected with the first flow divider inlet side, the first flow divider outlet is divided into two paths, one path is connected with the heat medium inlet side of a heat exchanger which exchanges heat with a heat user, the other path is sequentially connected with the third evaporator heat medium side inlet and the second evaporator heat medium side outlet, the first mixer inlet side is connected with the heat medium side outlet of the heat exchanger which exchanges heat with the heat user and the second evaporator heat medium side outlet, the low-temperature heat storage tank inlet side is connected with the first mixer outlet, the low-temperature heat storage tank outlet side is connected with the second working medium pump inlet side, and the second working medium pump outlet side is connected with the fourth heat exchanger cold medium side inlet.

[0020] The liquid hydrogen cold energy utilization system comprises a Brayton cycle power generation system, a Rankine cycle power generation system and an intermediate cold carrier circulation system which are sequentially arranged along a liquid hydrogen pipeline.

[0021] 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 sequentially connected in circulation; the Brayton cycle power generation system exchanges heat with seawater through the first seawater heat exchanger and exchanges heat with the liquid hydrogen pipeline through the first heat exchanger.

[0022] The Brayton cycle power generation system takes helium as a working medium, and the power generation process is as follows: the helium which is pressurized by the third compressor enters the first seawater heat exchanger to exchange heat with seawater, is heated and then enters the third expander to generate power, the helium which is expanded and generates power enters the first heat exchanger and the liquid hydrogen pipeline to exchange heat, the liquid hydrogen is gasified, and the cooled helium enters the third compressor again to complete the closed Brayton power generation cycle.

[0023] The Rankine cycle power generation system comprises a fourth working medium pump, a second seawater heat exchanger, a fourth expander and a second heat exchanger which are sequentially connected in circulation; the Rankine cycle power generation system exchanges heat with seawater through the second seawater heat exchanger and exchanges heat with the liquid hydrogen pipeline through the second heat exchanger.

[0024] The Rankine cycle power generation system takes propane as a working medium, and the power generation process is as follows: the liquid propane which is pressurized by the fourth working medium pump enters the second seawater heat exchanger to exchange heat with seawater, is gasified after heat exchange, the gaseous propane enters the fourth expander to generate power, the gaseous propane which is expanded and generates power enters the second heat exchanger to exchange heat with hydrogen, is cooled to liquid propane, and the liquid propane enters the fourth working medium pump again to complete the closed Rankine power generation cycle.

[0025] The intermediate cold carrier circulation system comprises a third heat exchanger and a sixth heat exchanger which are connected in circulation; the intermediate cold carrier circulation system absorbs the cold energy of the liquid hydrogen pipeline through the third heat exchanger and releases the cold energy through the sixth heat exchanger to cool a data center room.

[0026] The intermediate cold carrier circulation system uses glycol water solution as working medium, the cold carrier working medium absorbs the residual 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.

[0027] The fuel cell waste heat utilization system comprises a fourth compressor, a second throttling valve and a fifth heat exchanger connected in sequence.

[0028] The working process of the fuel cell waste heat utilization system is as follows: the gaseous working medium is pressurized by the fourth compressor, the temperature is increased, the gaseous working medium is liquefied by entering the fourth heat exchanger, the heat is released to the working medium of the high-temperature energy storage system, the liquid working medium enters the second throttling valve to be throttled and cooled, the pressure is reduced, the liquid working medium enters the fifth heat exchanger to be heated and gasified by the waste heat of the fuel cell reactor, and the gaseous working medium enters the fourth compressor again to complete the steam compression heat pump cycle.

[0029] Preferably, the working medium of the charging system is a mixture of argon and ethane, and the cycle is a steam compression refrigeration cycle.

[0030] Preferably, the working medium of the discharging system is a mixture of argon and ethane, and the cycle is a Rankine cycle.

[0031] 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.

[0032] The application also provides a multi-supply method based on the multi-supply system, and the operation strategy is as follows:

[0033] During the low electricity consumption period, the charging system, the liquid hydrogen cold energy utilization system and the fuel cell waste heat utilization system are operated, the excess power of the power grid, the electric energy of the liquid hydrogen cold energy utilization system and the fuel cell reactor are input into the compressor, the electric energy is converted into cold energy and stored in the low-temperature energy storage system, and the waste heat of the fuel cell reactor is stored in the high-temperature energy storage system after being upgraded in grade by the steam compression heat pump.

[0034] During the high electricity consumption period, the discharging system is operated, the stored cold energy and heat energy are converted into electric energy, and the electric energy is supplied to users.

[0035] During the cooling season, the flow ratio of the low-temperature energy storage system diverter is adjusted according to the user demand, part of the cold energy is supplied to cold users.

[0036] During the heating season, the flow ratio of the high-temperature energy storage system diverter is adjusted according to the user demand, part of the heat energy is supplied to hot users.

[0037] Compared with the prior art, the application has the following beneficial effects:

[0038] (1) The charging process in the application converts the excess power of the power grid, the power generated by the liquid hydrogen cold energy power generation and the power generated by the fuel cell into cold energy for storage, and the stored cold energy is converted into electric energy again in the discharging process, realizing the effective conversion of electric energy and cold energy. The multi-coupling supply system of the application can realize peak load shifting, reduce the pressure of the power grid load peak period, balance the load fluctuation of the power grid and ensure the stable operation of the power system.

[0039] (2) The application realizes the Carnot battery energy storage, and utilizes the large amount of cold energy generated in the liquid hydrogen gasification process and the large amount of heat energy released by the fuel cell of the hydrogen terminal user while generating electric energy, so as to reduce energy waste and avoid environmental pollution.

[0040] (3) The application realizes the gasification of liquid hydrogen, meets the supply of hydrogen to downstream users, and utilizes the high, medium and low grade cold energy in the liquid hydrogen gasification process to avoid cold energy waste and improve energy utilization efficiency.

[0041] (4) The high-temperature energy storage system and the low-temperature energy storage system of the application can adjust the supply according to the cold and heat energy demand of the user in the charging and discharging process, and construct a cold-heat-electricity combined supply comprehensive energy system. BRIEF DESCRIPTION OF DRAWINGS

[0042] Figure 1 The structure schematic view of the integrated Carnot battery energy storage and liquid hydrogen cold energy multi-coupling supply system provided for the embodiment of the application is shown in the figure.

[0043] Marked for explanation: 1, first compressor; 2, first condenser; 3, second compressor; 4, second condenser; 5, first throttle valve; 6, first evaporator; 7, first working medium 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 medium pump; 16, fourth heat exchanger; 17, high-temperature heat storage tank; 18, first flow divider; 19, heat user heat exchanger; 20, second throttle valve; 21, fifth heat exchanger; 22, fourth compressor; 23, fifth working medium pump; 24, first heat exchanger; 25, second heat exchanger; 26, third heat exchanger; 27, heater; 28, third compressor; 29, first seawater heat exchanger; 30, third expander; 31, fourth working medium pump; 32, second seawater heat exchanger; 33, fourth expander; 34, sixth heat exchanger; 35, high-temperature cold storage tank; 36, third working medium pump; 37, low-temperature cold storage tank; 38, second flow divider; 39, cold user heat exchanger; 40, second mixer; 41, fuel cell reactor. DETAILED DESCRIPTION

[0044] With reference to the accompanying drawings, the technical solutions in the embodiments of the present application will be described clearly and completely. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all the other embodiments obtained by those ordinarily skilled in the art without creative work fall within the scope of the present application.

[0045] The present application aims to provide a multi-supply system and method integrating Carnot battery energy storage and liquid hydrogen cold energy, which can not only realize efficient, stable, economic and safe energy storage, but also effectively reduce energy waste by utilizing cold energy in the liquid hydrogen gasification process.

[0046] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the present application will be further described in detail below with reference to the drawings and specific embodiments.

[0047] Reference Figure 1 As shown in the drawings, the present embodiment provides a multi-supply system integrating Carnot battery energy storage and liquid hydrogen cold energy, which comprises a charging process, a discharging process, a high-temperature energy storage system, a low-temperature energy storage system, a liquid hydrogen cold energy utilization system and a fuel cell waste heat utilization system.

[0048] In the specific use process, the charging process comprises 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 throttling valve 5 and a first evaporator 6 for heat exchange with 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, and 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 throttling valve 5, so as to utilize the cold energy in the liquid hydrogen gasification process for heat exchange with the working medium. The outlet of the first throttling valve 5 is connected to the cold medium inlet side of the first evaporator 6, so as to exchange heat between the cold energy of the liquid working medium in the charging process and the working medium in the low-temperature energy storage process. The cold medium outlet side of the first evaporator 6 is connected to the inlet of the first compressor 1.

[0049] In the embodiment, specifically, during the charging process, the electric energy from the low load of the power grid, the electric energy from the cold energy generated in the liquid hydrogen gasification process, and the electric energy from the fuel cell power generation drive the first compressor 1 and the second compressor 3. The first compressor 1 compresses the working medium, so that the temperature and pressure of the working medium are increased. The high-temperature and high-pressure gaseous working medium enters the first condenser 2 and the liquid hydrogen gasification pipeline for heat exchange, and then enters the second compressor 3 after the temperature is reduced. The high-temperature and high-pressure gaseous working medium enters the second condenser 4 and the liquid hydrogen gasification pipeline for heat exchange again. The cold energy liquefies the gaseous working medium. The liquid working medium enters the first throttling valve 5 for further throttling and cooling, so as to increase the supercooling degree of the working medium. The low-temperature and low-pressure liquid working medium enters the first evaporator 6 and the working medium of the low-temperature energy storage process for heat exchange, so as to transfer the cold energy to the low-temperature energy storage working medium. The working medium is gasified again and then enters the first compressor 1, so as to complete the steam compression refrigeration cycle of the charging process.

[0050] In the embodiment, specifically, during the discharging process, the first working medium pump 7, the first expander 9, the second expander 11, the third condenser 12 for heat exchange with the cold storage side, the second evaporator 8 for heat exchange with the heat storage side, and the third evaporator 10 are included. The inlet and outlet of the refrigerant side of the second evaporator 8 are respectively connected to the outlet of the first working medium pump 7 and the inlet of the first expander 9. The inlet and outlet of the refrigerant side of the third evaporator 10 are respectively connected to the outlet of the first expander 9 and the inlet of the second expander 11. The outlet of the second expander 11 is connected to the inlet of the heat medium side of the third condenser 12. The outlet of the heat medium side of the third condenser 12 is connected to the inlet of the first working medium pump 7.

[0051] In the embodiment, specifically, during the discharging process, the gaseous working medium of the discharging process is cooled and liquefied by the low-temperature energy storage working medium through the third condenser 12. The liquid working medium is pressurized by the first working medium pump 7 and then enters the second evaporator 8. The gaseous working medium is heated and gasified by the high-temperature energy storage process working medium in the second evaporator 8. The gaseous working medium enters the first expander 9 to generate power. The low-temperature working medium from the first expander 9 enters the third evaporator 10, is heated by the third evaporator 10, and then enters the second expander 11 to generate power. The cold energy is converted into electric energy. The low-temperature and low-pressure working medium after power generation enters the third condenser 12, so as to complete the Rankine cycle of the discharging process.

[0052] In this embodiment, specifically, the high-temperature thermal storage system includes a high-temperature thermal storage tank 17, a low-temperature thermal storage tank 14, a second working medium pump 15, a first mixer 13 and a first flow divider 18. The high-temperature thermal storage tank 17 is connected to the outlet side of the fourth heat exchanger 16 of the heat release side of the vapor compression heat pump. The outlet of the high-temperature thermal storage tank 17 is connected to the inlet of the first flow divider 18. The outlet of the first flow divider 18 is connected to the inlet of the heat user heat exchanger 19 and the inlet of the third evaporator 10 of the discharging process. The inlet side of the first mixer 13 is connected to the outlet of the heat user heat exchanger 19 and the outlet of the second evaporator 8 of the discharging process. The inlet and outlet sides of the low-temperature thermal storage tank 14 are connected to the outlet of the first mixer 13 and the inlet side of the second working medium pump 15, respectively. The outlet side of the second working medium pump 15 is connected to the inlet of the fourth heat exchanger 16 of the heat release side of the vapor compression heat pump.

[0053] In this embodiment, specifically, the high-temperature thermal storage system includes a high-temperature thermal storage tank 17, a low-temperature thermal storage tank 14, a second working medium pump 15, a first mixer 13 and a first flow divider 18. The high-temperature thermal storage tank 17 is connected to the outlet side of the fourth heat exchanger 16 of the heat release side of the vapor compression heat pump. The outlet of the high-temperature thermal storage tank 17 is connected to the inlet of the first flow divider 18. The outlet of the first flow divider 18 is connected to the inlet of the heat user heat exchanger 19 and the inlet of the third evaporator 10 of the discharging process. The inlet side of the first mixer 13 is connected to the outlet of the heat user heat exchanger 19 and the outlet of the second evaporator 8 of the discharging process. The inlet and outlet sides of the low-temperature thermal storage tank 14 are connected to the outlet of the first mixer 13 and the inlet side of the second working medium pump 15, respectively. The outlet side of the second working medium pump 15 is connected to the inlet of the fourth heat exchanger 16 of the heat release side of the vapor compression heat pump.

[0054] In this embodiment, specifically, the low-temperature thermal storage system includes a high-temperature cold storage tank 35, a low-temperature cold storage tank 37, a third working medium pump 36, a second mixer 40 and a second flow divider 38. The inlet and outlet sides of the low-temperature cold storage tank 37 are connected to the outlet of the first evaporator 6 of the charging process and the inlet of the second flow divider 38, respectively. The outlet of the second flow divider 38 is connected to the inlet of the cold user heat exchanger 39 and the inlet of the third condenser 12 of the discharging process. The inlet side of the second mixer 40 is connected to the outlet of the cold user heat exchanger 39 and the outlet of the third condenser 12 of the discharging process. The inlet and outlet sides of the high-temperature cold storage tank 35 are connected to the outlet of the second mixer 40 and the inlet side of the third working medium pump 36, respectively. The outlet side of the third working medium pump 36 is connected to the inlet side of the first evaporator 6 of the charging process.

[0055] In this embodiment, specifically, the low-temperature storage refrigerant in the low-temperature storage tank 37 enters the second flow divider 38, and the flow ratio of the refrigerant flowing to the heat exchanger 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 energy and meet the cooling demand of the cold user. After the cold energy is released, the refrigerant flows to the high-temperature storage tank 35 through the second mixer 40, and the storage medium in the high-temperature storage tank 35 is pressurized by the third working medium pump 36 and then enters the first evaporator 6 in the charging process to absorb the cold energy from the charging process, and then enters the low-temperature storage tank 37 for cold storage.

[0056] In this embodiment, specifically, the liquid hydrogen cold energy utilization system includes a Brayton power generation cycle, a Rankine power generation cycle, a data center cooling cycle, a first condenser 2 and a second condenser 4 of the charging process, and a liquid hydrogen pipeline heat exchanger 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 medium as follows: the helium is pressurized by the third compressor 28 in turn and then enters the first seawater heat exchanger 29 to exchange heat with seawater, is warmed, and then enters the third expander 30 to generate power, and the helium after expansion and power generation enters the first heat exchanger 24 and exchanges heat with liquid hydrogen, and the liquid hydrogen is gasified, and 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 medium is as follows: the liquid propane is pressurized by the fourth working medium pump 31 and then sent to the second seawater heat exchanger 32, is gasified after heat exchange with seawater, the gaseous propane enters the fourth expander 33 to generate power, and the gaseous propane after expansion and power generation is cooled to liquid propane after heat exchange with hydrogen in the second heat exchanger 25, and the liquid propane enters the fourth working medium pump 31 again to complete the closed Rankine power generation cycle; the data center cooling cycle using ethylene glycol water solution as the working medium is as follows: the ethylene glycol water solution exchanges heat with hydrogen in the third heat exchanger 26, is cooled, and then enters the sixth heat exchanger 34 to release cold energy to the data center room, and the ethylene glycol water solution after being warmed enters the third heat exchanger again to complete the data center cooling cycle.

[0057] In this embodiment, specifically, the function of the heater 27 is to adjust the temperature of the hydrogen gas, and the outlet hydrogen gas temperature can be adjusted according to different terminal requirements to achieve flexible gas supply.

[0058] In this embodiment, specifically, the fuel cell waste heat utilization system includes a fuel cell reactor 41 and a steam compression heat pump cycle to provide heat energy for the discharge process, the gaseous working medium is pressurized by the fourth compressor 22 to increase the temperature, enters the fourth heat exchanger 16 to liquefy, and releases heat to the high-temperature storage system working medium, the liquid working medium is throttled and cooled by the second throttle valve 20, the pressure is reduced, enters the fifth heat exchanger 21, and is gasified by the fuel cell waste heat, and the gaseous working medium enters the fourth compressor 22 again to complete the steam compression heat pump cycle, and the fuel cell waste heat grade is improved.

[0059] In the embodiment, specifically, the working substance of the charging process is a mixture of argon and ethane, and the cycle is a vapor compression refrigeration cycle.

[0060] In the embodiment, specifically, the working substance of the discharge process is a mixture of argon and ethane, and the cycle is a Rankine cycle.

[0061] In the 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.

[0062] In the embodiment, specifically, the multi-supply method integrating the Carnot cell energy storage and liquid hydrogen cold energy includes charging, discharging, heat supply, and cold supply, and the specific operation strategy is as follows:

[0063] During the low electricity consumption period, the charging process, the liquid hydrogen cold energy utilization system, and the fuel cell waste heat utilization system are operated. The charging process inputs the excess power of the power grid, the power generated by the liquid hydrogen cold energy, and the power generated by the fuel cell into the compressor. 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 stored in the high-temperature energy storage system after being upgraded in grade by the vapor compression heat pump.

[0064] During the high electricity consumption period, the discharge process is operated. The stored cold energy and heat energy are converted into electric energy and supplied to users.

[0065] During the cold supply season, the flow ratio of the low-temperature energy storage system flow divider is adjusted according to the user demand. Part of the cold energy is supplied to cold users.

[0066] During the heat supply season, the flow ratio of the high-temperature energy storage system flow divider is adjusted according to the user demand. Part of the heat energy is supplied to hot users.

[0067] The above-described embodiments have described the technical solutions and beneficial effects of the present application in detail. It should be understood that the above-described embodiments are only specific embodiments of the present application and are not used to limit the present application. Any modification, supplement, and equivalent replacement within the principle range of the present application should be included in the protection range of the present application.

Claims

1. An integrated Carnot cell energy storage and liquid hydrogen cold energy multi -supply system, characterized in that, The system comprises a charging system, a 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 and a first throttling valve connected in sequence and circulating. The discharging system comprises a first working medium pump, a second evaporator, a first expander, a third evaporator, a second expander and a third condenser connected in sequence and circulating. The low-temperature energy storage system comprises a high-temperature cold storage tank and a low-temperature cold storage tank. The high-temperature cold storage tank and the low-temperature cold storage tank are connected in series. The high-temperature energy storage system comprises a high-temperature heat storage tank and a low-temperature heat storage tank. The high-temperature heat storage tank and the low-temperature heat storage tank are connected in series. The liquid hydrogen cold energy utilization system comprises a power generation cycle system. The fuel cell waste heat utilization system absorbs the waste heat of a fuel cell reactor through a steam compression heat pump cycle to provide heat energy for the discharging system. The low-temperature energy storage system comprises a high-temperature cold storage tank, a third working medium pump, a low-temperature cold storage tank, a second mixer and a second flow divider connected in series and circulating. The low-temperature cold storage tank is connected to the first evaporator. The third condenser is connected to the second flow divider. The second mixer is connected to the heat exchanger and the third condenser. The high-temperature cold storage tank is connected to the second mixer. The high-temperature cold storage tank is connected to the heat exchanger and the third condenser. The third working medium pump is connected to the first evaporator. The high-temperature energy storage system comprises a low-temperature heat storage tank, a second working medium pump, a fourth heat exchanger, a high-temperature heat storage tank, a first mixer and a first flow divider which are connected in sequence; the high-temperature heat storage tank is connected with the fourth heat exchanger on the cold medium outlet side, and the high-temperature heat storage tank is connected with the first flow divider on the inlet side; the outlet of the first flow divider is connected with a heat exchanger on the hot medium inlet side for heat exchange with a heat user in one way, and is connected with a third evaporator hot medium side inlet and a second evaporator hot medium side outlet in another way; the inlet side of the first mixer is connected with the heat exchanger hot medium side outlet and the second evaporator hot medium side outlet; the low-temperature heat storage tank is connected with the outlet of the first mixer on the inlet side, and the outlet side of the low-temperature heat storage tank is connected with the inlet side of the second working medium pump; the outlet side of the second working medium pump is connected with the fourth heat exchanger on the cold medium side inlet; The liquid hydrogen cold energy utilization system comprises a Brayton cycle power generation system, a Rankine cycle power generation system and an intermediate cold carrier circulation system which are arranged in sequence along a liquid hydrogen pipeline; 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 sequence; the first seawater heat exchanger absorbs seawater heat, and the first heat exchanger exchanges heat with the liquid hydrogen pipeline; the Rankine cycle power generation system comprises a fourth working medium pump, a second seawater heat exchanger, a fourth expander and a second heat exchanger which are connected in sequence; the second seawater heat exchanger absorbs seawater heat, and the second heat exchanger exchanges heat with the liquid hydrogen pipeline; the intermediate cold carrier circulation system comprises a third heat exchanger and a sixth heat exchanger which are connected in sequence; the third heat exchanger absorbs the cold energy of the liquid hydrogen pipeline, and the sixth heat exchanger releases the cold energy; The fuel cell waste heat utilization system comprises a fourth compressor, a second throttling valve and a fifth heat exchanger which are connected in sequence; the passage between the second throttling 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 throttling valve inlet provides heat energy for the high-temperature energy storage system through the fourth heat exchanger.

2. The integrated Carnot cell energy storage and liquid hydrogen cold energy multi -generation system according to claim 1, characterized in that, The working medium of the charging system is a mixture of argon and ethane, and the cycle is a vapor compression refrigeration cycle; the working medium of the discharging system is a mixture of argon and ethane, and the cycle is a Rankine cycle.

3. The integrated Carnot cell energy storage and liquid hydrogen cold energy multi -generation system of claim 1, wherein, 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.

4. A poly-generation method based on the poly-generation system according to any one of claims 1-3, characterized in that, The operation strategy is as follows: During the low electricity consumption period, the charging system, the liquid hydrogen cold energy utilization system and the fuel cell waste heat utilization system are operated, the excess power of the power grid, the liquid hydrogen cold energy utilization system and the electric energy of the fuel cell reactor are input into the compressor, the electric energy is converted into cold energy and stored in the low-temperature energy storage system, and the waste heat of the fuel cell reactor is stored in the high-temperature energy storage system after being upgraded in grade by the vapor compression heat pump; During the high electricity consumption period, the discharging system is operated, the stored cold energy and heat energy are converted into electric energy, and the electric energy is supplied to the user; During the cooling season, the flow ratio of the low-temperature energy storage system flow divider is adjusted according to the user demand, part of the cold energy is supplied to the cold user; During the heating season, the flow ratio of the high-temperature energy storage system flow divider is adjusted according to the user demand, part of the heat energy is supplied to the heat user.

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