Advanced liquefied air energy storage system coupled with various cold and hot electric energy and operation method

Abstract

The invention relates to an advanced liquefied air energy storage system coupled with various cold and hot electric energy and an operation method. The system comprises a compressor subsystem, a liquefaction subsystem, an expansion machine subsystem, a heat storage subsystem and an external energy subsystem. The compressor subsystem is connected with the liquefaction subsystem; the liquefaction subsystem is connected with the expansion machine subsystem at the same time; the compressor subsystem is bidirectionally connected with the heat storage subsystem at the same time to realize transmission of heat energy or cold energy; the expansion machine subsystem is bidirectionally connected with the heat storage subsystem at the same time to realize transmission of heat energy or cold energy; and the external energy subsystem is bidirectionally connected with the heat storage subsystem to realize energy exchange of external heat energy or cold energy. According to the system, cold energy and electric energy released by the external energy subsystem, cold energy and heat energy of the liquefaction compression system, compression heat energy of the hydrogen liquefaction system and other energy are fully utilized, cyclic utilization of the cold energy, the heat energy and the electric energy is achieved, and the overall comprehensive efficiency of the system is greatly improved.

Description

Technical Field

[0001] The present invention belongs to the field of energy storage technology, and in particular relates to an advanced liquefied air energy storage system and an operation method for coupling multiple cold, hot and electric energies. Background Art

[0002] Under the dual carbon goals, the proportion of new energy is increasing rapidly, and the impact of new energy instability on the power grid is gradually increasing. It is urgent to build large-scale long-term energy storage to provide key support for the stable operation of the new power system. As a long-term energy storage type, liquefied compressed air energy storage has the advantages of high energy storage density, long operating life, and flexible site selection and layout, and has gradually attracted the attention of the industry.

[0003] LNG (liquefied natural gas) needs to be vaporized when supplying natural gas on the demand side, and a large amount of cold energy will be released during the vaporization process. At present, the vaporization process mostly uses seawater to directly take away the cold energy, resulting in a large amount of cold energy loss and pollution near the sea. Similarly, hydrogen, as an important energy source, is widely used in the aerospace industry by liquefying and storing hydrogen. Hydrogen will generate a large amount of compression heat during the liquefaction process. At the same time, the liquefaction process also requires a large amount of cold energy and electricity. ORC (Organic Rankine Cycle) is a Rankine cycle that uses low-boiling point organic matter as a working fluid. It is an effective way to generate low-temperature waste heat, improve energy utilization efficiency, and reduce environmental pollution.

[0004] The liquefaction process is an important process in liquefied compressed air energy storage. The liquefaction process is used to convert gaseous air into liquid air. This process consumes a lot of energy, resulting in low system efficiency. For this reason, some scholars have improved the liquefied compressed air energy storage system by coupling LNG systems, ORC systems, etc., but the effect is minimal. Summary of the invention

[0005] In order to overcome the above problems existing in the prior art, the present invention provides an advanced liquefied air energy storage system and an operation method for coupling multiple cold, hot and electric energies.

[0006] An advanced liquefied air energy storage system coupling multiple cold, hot and electric energies, the system comprising: a compressor subsystem, a liquefaction subsystem, an expander subsystem, a heat storage subsystem and an external energy subsystem;

[0007] Wherein, the compressor subsystem is connected to the liquefaction subsystem;

[0008] The liquefaction subsystem is simultaneously connected to the expander subsystem;

[0009] The compressor subsystem is bidirectionally connected to the heat storage subsystem to achieve the transmission of heat energy or cold energy;

[0010] The expander subsystem is bidirectionally connected to the heat storage subsystem to achieve the transmission of cold energy or heat energy;

[0011] The external energy subsystem is bidirectionally connected to the heat storage subsystem to achieve energy exchange of external heat energy or cold energy.

[0012] According to the above aspects and any possible implementations, an implementation is further provided, wherein the external energy subsystem includes a liquefied natural gas (LNG) subsystem, an organic Rankine cycle (ORC) power generation subsystem, and a hydrogen liquefaction subsystem.

[0013] According to the aspects described above and any possible implementation, an implementation is further provided, wherein the compressor subsystem includes a first compressor, an air filter, a first motor and a first cooler, wherein the air filter is connected to the first compressor, and the first compressor is connected to the first cooler and the first motor at the same time.

[0014] According to the aspects described above and any possible implementation, there is further provided an implementation, wherein the expander subsystem includes a first air turbine, a first regenerator, and an air heater connected in sequence.

[0015] According to the aspects described above and any possible implementation methods, an implementation method is further provided, wherein the liquefaction subsystem includes a multi-stream energy flow heat exchanger, a throttle valve, a gas-liquid separator, a liquefied air storage tank, a first evaporator, a second cold storage medium pump, a first cold storage medium storage tank and a first cold storage medium storage tank, wherein the multi-stream energy flow heat exchanger is connected to the first cooler and connected to the gas-liquid separator through the throttle valve, the multi-stream energy flow heat exchanger is also connected to the first cold storage medium storage tank and the second cold storage medium storage tank, the gas-liquid separator is connected to the liquid air storage tank, the liquid air storage tank is connected to the first evaporator, and the first evaporator is also connected to the first cold storage medium storage tank and the second cold storage medium storage tank through the second cold storage medium pump.

[0016] According to the aspects described above and any possible implementation, an implementation is further provided, wherein the ORC power generation subsystem includes a preheater, a second evaporator, a second air turbine, a first condenser, a fifth cold medium pump and a second generator, wherein the preheater is connected to the second evaporator, the second evaporator is connected to the second air turbine, the second air turbine is connected to the first condenser, the second air turbine is also connected to the second generator, and the first condenser is connected to the fifth cold medium pump.

[0017] According to the aspects described above and any possible implementation method, an implementation method is further provided, wherein the LNG subsystem includes an LNG storage tank, an LNG pump, a third switch valve, a fourth switch valve, a fifth switch valve, a sixth switch valve and a gaseous natural gas user, the LNG storage tank is connected to the LNG pump, the LNG pump is connected to the first condenser through the third switch valve and the sixth switch valve, the LNG pump is connected to the multiple energy flow heat exchanger through the fourth switch valve, and the multiple energy flow heat exchanger is connected to the gaseous natural gas user through the fifth switch valve.

[0018] According to the aspects described above and any possible implementation method, an implementation method is further provided, wherein the hydrogen liquefaction subsystem includes a second compressor, a second cooler, a hydrogen precooling device, a liquid hydrogen storage tank, a second motor and an eighth switch valve, the second compressor is connected to the second cooler, the second compressor is also connected to the second motor, the second cooler is connected to the hydrogen precooling device, and the hydrogen precooling device is connected to the liquid hydrogen storage tank.

[0019] According to the aspects described above and any possible implementation, an implementation is further provided, wherein the heat storage subsystem includes a first heat medium storage tank, a second cold medium storage tank, a third heat medium pump, a fourth cold medium pump, a sixth cold medium pump, and a sixth heat medium pump; the second cold medium storage tank is connected to the first cooler and the second evaporator through the fourth cold medium pump, and is connected to the second cooler and the first heat regenerator through the sixth cold medium pump; the first heat medium storage tank is connected to the first cooler, is connected to the first heat regenerator through the third heat medium pump, is connected to the preheater through the sixth heat medium pump, and is connected to the second cooler through the eighth switch valve.

[0020] The present invention also provides an operation method of an advanced liquefied air energy storage system that couples multiple cold, hot and electric energies. The method is implemented using the system, and the method includes an energy storage process and an energy release process.

[0021] Beneficial effects of the present invention

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] (1) The present invention provides a liquefied compressed air energy storage system that integrates multiple cold energy, heat energy, and electric energy, and fully utilizes the cold energy released by the LNG subsystem, the cold energy and heat energy of the liquefaction subsystem, the compressed heat energy of the hydrogen liquefaction subsystem, and the electric energy of the ORC subsystem, thereby realizing the recycling of cold energy, heat energy, and electric energy, and greatly improving the overall comprehensive efficiency of the system.

[0024] (2) The compressed air energy storage operation method of the present invention realizes switching between different systems according to the electricity price policy of the region by setting multiple valves, thereby realizing the operation or shutdown of a single system or multiple systems, maximizing the utilization of resources such as electricity, and improving the operating benefits of the power station.

[0025] (3) The energy storage system provided by the present invention greatly reduces the number of equipment such as heat exchangers, storage tanks, and pipelines by sharing equipment among subsystems, reduces the land occupied by the power station, and thus reduces the investment cost of the power station. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is the overall structural block diagram of the system of the present invention;

[0027] Figure 2 It is a schematic diagram of the overall structure of the system of the present invention. DETAILED DESCRIPTION

[0028] In order to better understand the technical solution of the present invention, the content of the present invention includes but is not limited to the specific implementation methods described below, and similar technologies and methods should be considered to be within the scope of protection of the present invention. In order to make the technical problems, technical solutions and advantages to be solved by the present invention clearer, the following will be described in detail with reference to the accompanying drawings and specific embodiments.

[0029] It should be clear that the embodiments described in the present invention are only part of the embodiments of the present invention, rather than all 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.

[0030] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. The singular forms "a", "said" and "the" used in the embodiments of the present invention and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

[0031] like Figure 1 As shown, the present invention is an advanced liquefied air energy storage system that couples multiple cold, hot and electric energies. The liquefied compressed air energy storage system includes a compressor subsystem, a liquefaction subsystem, an expander subsystem, a heat storage subsystem and an external energy subsystem.

[0032] The compressor subsystem is connected to the liquefaction subsystem, and the compressor subsystem compresses ambient air into high-pressure and high-temperature air;

[0033] The liquefaction subsystem is connected to the expander subsystem, and the liquefaction subsystem converts gaseous ambient air into liquid air;

[0034] The compressor subsystem is bidirectionally connected to the heat storage subsystem. The heat medium storage tank in the heat storage subsystem is mainly used to store the heat medium after the cold storage medium is exchanged with high-temperature air during the energy storage process. The cold medium storage tank is mainly used to store the cold medium after the heat storage medium is exchanged with low-temperature air during the energy release process. A heat storage medium pump is provided between the compressor subsystem and the heat storage subsystem to realize the transmission of heat energy and cold energy.

[0035] The expander subsystem is bidirectionally connected to the heat storage subsystem, and a heat storage medium pump is provided between the expander subsystem and the heat storage subsystem to realize the transmission of heat energy and cold energy. The expansion subsystem uses high-temperature and high-pressure air to drive the air turbine impeller to work, thereby driving the generator to work and generate electricity.

[0036] The external energy subsystem is bidirectionally connected to the heat storage subsystem to realize the energy exchange between external heat energy, cold energy and the heat storage subsystem. A switch valve is provided between the external energy subsystem and the heat storage subsystem to realize the interaction between the two subsystems. The external energy subsystem realizes LNG vaporization for natural gas users, ORC power generation, and liquid hydrogen vaporization. The LNG process, ORC power generation process, and liquefaction process will all generate heat and cold energy, which are used in the compressed air liquefaction process.

[0037] The external energy subsystem includes an LNG subsystem, an ORC power generation subsystem and a hydrogen liquefaction subsystem. The LNG subsystem mainly realizes the conversion of liquid natural gas into gaseous natural gas, and generates a large amount of cold energy during the vaporization process, which is used in the liquefaction compression process.

[0038] The ORC power generation subsystem mainly realizes the vaporization and liquefaction process of the liquid working medium, generates electrical energy, and is incorporated into the power grid or used in the hydrogen liquefaction process.

[0039] The hydrogen liquefaction subsystem mainly converts liquid hydrogen into gaseous hydrogen.

[0040] like Figure 2 As shown, the compressor subsystem includes a first compressor 2, an air filter 1, a first motor 4, and a cooler 3. The first compressor 2 is one or more compressors, each of which includes two or more compressors, each compressor includes multiple stages, and the pressure is continuously increased after multiple stages of compression. The air filter 1 is connected to the first compressor 2, the first compressor 2 is connected to the air side inlet of the first cooler 3, the first compressor 2 is also connected to the first motor 4, and the air side outlet of the first compressor 2 is connected to the multi-stream energy flow heat exchanger 9 of the liquefaction subsystem below.

[0041] The expander subsystem includes an air turbine 5, a regenerator 6 and an air heater 7. The air turbine 5 is a multi-stage air turbine. The first regenerator 6 is connected to the first air turbine 5. The air heater 7 heats the air before entering the air turbine 5 to improve the work capacity. Figure 2 It can be seen that the air heater 7 is set in a parallel route, and whether to perform the heating operation is determined according to the heat in the hot water storage tank, so the air heater 7 is connected to the air turbine 5 through the regenerator 6.

[0042] The heat storage subsystem is mainly a storage tank, and the heat storage medium uses pressurized water, heat transfer oil and molten salt medium, including a first heat medium storage tank 17, a second cold medium storage tank 18, a third heat medium pump 19, a fourth cold medium pump 20, a sixth cold medium pump 44, and a sixth heat medium pump 46. The second cold medium storage tank 18 is connected to the medium side inlet of the first cooler 3 of the compressor subsystem through the fourth cold medium pump 20, to the second evaporator 30 of the ORC power generation subsystem, to the second cooler 38 of the hydrogen liquefaction subsystem through the sixth cold medium pump 44, and to the medium side outlet of the first regenerator 6 of the expander subsystem. The first heat medium storage tank 17 is connected to the medium side outlet of the first cooler 3 of the compressor subsystem, to the medium side inlet of the first regenerator 6 of the expander subsystem through the third heat medium pump 19, to the preheater 29 of the ORC power generation subsystem through the sixth heat medium pump 46, and to the second cooler 38 of the hydrogen liquefaction subsystem through the eighth switch valve 45.

[0043] The liquefaction subsystem includes a multi-stream energy flow heat exchanger 9, a throttle valve 24, a gas-liquid separator 10, a liquefied air storage tank 11, a first evaporator 12, a first cold storage medium storage tank 13, and a second cold storage medium storage tank 14. The multi-stream energy flow heat exchanger 9 is connected to multiple components, specifically: the inlet is connected to the first cooler 3 of the compressor subsystem; it is connected to the gas-liquid separator 10 through the throttle valve 24, the gas-liquid separator 10 is connected to the multi-stream energy flow heat exchanger 9 through the throttle valve 24, the multi-stream energy flow heat exchanger 9 is also connected to the first cold storage medium storage tank 13, and is connected to the second cold storage medium storage tank 14 through the first cold storage medium pump 15, the gas-liquid separator 10 is also connected to the inlet of the liquid air storage tank 11 at the same time, the outlet of the liquid air storage tank 11 is connected to the first evaporator 12, the first evaporator 12 is also connected to the first cold storage medium storage tank 13 through the second cold storage medium pump 16, and is directly connected to the second cold storage medium storage tank 14. The first evaporator 12 is connected to the air heater 7 of the expander subsystem through the first switch valve 22, and then connected to the first regenerator 6 of the expander subsystem. The first evaporator 12 can also be directly connected to the first regenerator 6 through the second switch valve 23. The multi-stream energy flow heat exchanger 9 is connected to multiple devices including a gas-liquid separator, an LNG storage tank, a first cold storage medium storage tank 13, and a second cold storage medium storage tank; the compressed air coming out of the first cooler is further cooled by the multi-stream energy flow heat exchanger and enters the gas-liquid separator. The cold energy required for cooling comes from the cold storage medium storage tank, and the cold energy in the cold storage medium storage tank comes from the process of converting air in the liquid air storage tank into gaseous air; the gaseous air separated by the gas-liquid separator is cooled by the multi-stream energy flow heat exchanger and then directly discharged into the air; the liquid natural gas in the LNG storage tank generates a large amount of cold energy during the vaporization process, and heat is exchanged with the compressed gaseous air in the multi-stream energy flow heat exchanger. The multi-stream energy flow heat exchanger is a heat exchange of multiple energies.

[0044] The LNG subsystem includes an LNG storage tank 25, an LNG pump 26, a third switch valve 27, a fourth switch valve 28, a fifth switch valve 34, a sixth switch valve 35 and a gaseous natural gas user 43. The LNG storage tank 25 is connected to the LNG pump 26, and the LNG pump 26 is connected to the first condenser of the ORC power generation subsystem through the third switch valve 27 and the sixth switch valve 35. The LNG pump 26 can also be connected to the multi-stream energy flow heat exchanger 9 of the liquefaction subsystem through the fourth switch valve 28, and the multi-stream energy flow heat exchanger 9 is connected to the gaseous natural gas user 43 through the fifth switch valve 34.

[0045] The ORC power generation subsystem includes a preheater 29, a second evaporator 30, a second air turbine 31, a first condenser 32, a fifth cold medium pump 33 and a second generator 36. The preheater 29 is connected to the second evaporator 30, the second evaporator 30 is connected to the second air turbine 31, the second air turbine 31 is connected to the first condenser 32, the second air turbine 31 is also connected to the second generator 36, and the first condenser 32 is connected to the preheater 29 through the fifth cold medium pump 33.

[0046] The hydrogen liquefaction subsystem includes a second compressor 37, a second cooler 38, a hydrogen precooling device 39, a liquid hydrogen storage tank 40, a second motor 42, a seventh switch valve 41, and an eighth switch valve 45. The second compressor 37 is connected to the second cooler 38, which is also connected to the second motor 42, the second cooler 38 is connected to the hydrogen precooling device 39, is connected to the second cold medium storage tank 18 through the sixth cold medium pump 44, is connected to the first hot medium storage tank 17 through the eighth switch valve 45, and the hydrogen precooling device 39 is connected to the liquid hydrogen storage tank 40.

[0047] The system further includes a power grid 21, which is connected to the first motor 4, the first generator 8, the second generator 36, and the second motor 42. The electric energy generated by the second generator 36 is directly incorporated into the power grid 21 or used to rotate the second compressor 37 during the hydrogen liquefaction process. The electric energy of the power grid 21 can be directly used to rotate the first compressor 2, or the electric energy generated by the first generator 8 can be directly incorporated.

[0048] like Figure 2 As shown, the present invention also discloses a method for operating a compressed air energy storage system for medium-temperature hot water heat storage, the operating method including a liquefied compressed air energy storage process, a liquefied compressed air energy release process, an LNG vaporization process, an ORC power generation process, a hydrogen liquefaction process and a switching process of energy utilization between different systems.

[0049] During off-peak electricity (low electricity price), the electric energy is stored in other forms of energy, and during peak electricity consumption (high electricity price), other forms of energy are converted into electric energy. Therefore, in this case, the liquefied compressed air energy storage process is as follows: the ambient air passes through the first filter 1 and enters the first compressor 2, and the off-peak electricity, abandoned wind and abandoned photovoltaic power of the power grid 21 are used to drive the first motor 4 that drives the compressor 2 to rotate, and the electric energy from the power grid 21 is converted into mechanical energy. The compressor 2 is driven by the first motor 4 to compress the air, and the compressed high-temperature and high-pressure air enters the first cooler 3, exchanges heat with the medium from the second cold medium storage tank 18, and cools the air. The hot medium after heat exchange is sent to the first hot medium storage tank 17 for storage, and the cooled air enters the multi-energy flow heat exchanger 9, and further exchanges heat with the cold medium from the second cold storage medium storage tank 14 or the cold energy after LNG vaporization of the fourth switch valve 28 of the LNG subsystem. The cold medium of the second cold storage medium storage tank 14 exchanges heat and is stored in the first cold storage medium storage tank 13. The air in the multi-stream energy flow heat exchanger 9 is further cooled after the heat exchange, and then enters the throttle valve 24, and is further cooled and depressurized by the throttle valve 24, and the gaseous air is converted into liquid air, and enters the gas-liquid separator 10, and then the liquid air enters the liquid air storage tank 11 from the gas-liquid separator 10 for storage, while the unliquefied air directly flows back to the multi-stream energy flow heat exchanger 9, and is directly discharged into the atmosphere after passing through the multi-stream energy flow heat exchanger 9, or is mixed with ambient air and sent to the first compressor 2. In this process, the compressor consumes electrical energy for compression, and the compressed air exchanges heat energy after passing through the cooler. After passing through the multi-stream energy flow heat exchanger, the cold energy is exchanged with the hot air. In this process, there is coupling of heat energy, cold energy and electrical energy. The cold energy comes from the second cold storage medium storage tank or the cold energy after LNG vaporization, so there is coupling of cold energy and liquefied air.

[0050] The energy storage and release process of the liquefied compressed air is as follows: the liquid air in the liquid air storage tank 11 is converted into gaseous air after being vaporized by the first evaporator 12, and the cold energy generated by vaporization is sent to the second cold storage medium storage tank 14. The gaseous air enters the first regenerator 6 through the second switch valve 23, and after exchanging heat with the heat medium from the first heat medium storage tank 17 through the third heat medium pump 19 in the first regenerator 6, it is converted into high-temperature and high-pressure air, enters the air turbine 5 to do work, drives the first generator 8 to generate electricity, and the electricity is incorporated into the power grid 21. At the same time, the heat medium after heat exchange is converted into cold medium and stored in the second cold medium storage tank 18. Preferably, when the air in the first evaporator 12 flows out, the air heater 7 can also be used to heat the air at the outlet of the first evaporator 12 through the first switch valve 22 to increase the temperature of the gaseous air, thereby improving the air's ability to do work. In the energy release process, after being heated, the air in the liquid gas storage tank does work in the air turbine, drives the generator to generate electricity, and heat energy is converted into electrical energy. At the same time, during the heating process, the heat energy in the first heat medium storage tank 17 exchanges heat in 6, and the cold energy after heat exchange is stored in the second cold medium storage tank 18, thereby achieving the coupling of heat energy, cold energy and electric energy.

[0051] The LNG vaporization process: the liquid natural gas in the LNG storage tank 25 generates a large amount of cold energy after passing through the LNG pump 26, and the cold energy enters the multi-stream energy flow heat exchanger 9 through the fourth switch valve 28; it can also be directly connected to the first condenser 32 or directly supplied to the gaseous natural gas user through the third switch valve 27. The choice of the third switch valve 27 or the fourth switch valve 28 depends on whether the cold energy in the multi-stream energy flow heat exchanger 9 is sufficient for use. If the cold energy from the second cold storage medium storage tank 14 is sufficient for the gaseous air liquefaction process from the first cooler 3, the line where the third switch valve 27 is located is directly selected; if not, the line where the fourth switch valve 28 is located is selected to use the cold energy in the LNG vaporization process. In the multi-stream energy flow heat exchanger 9, the cold energy exchanges heat with the compressed gaseous air, and the liquid natural gas after the heat exchange is connected to the first condenser 32 in the ORC subsystem. The medium in the ORC subsystem is its own circulating medium, which is different from other systems and can use R245fa working fluid.

[0052] The working fluid of the LNG subsystem is liquefied natural gas, the working fluid of the ORC subsystem is R245fa, and the working fluid of the liquefied subsystem is air.

[0053] The medium of the hydrogen subsystem is liquefied hydrogen. The liquefied natural gas further exchanges heat with the medium circulating in the ORC subsystem itself, is converted into gaseous natural gas, and enters the natural gas pipeline (i.e., the pipeline before entering the gaseous natural gas user 43) for use by the gaseous natural gas user 43.

[0054] The ORC power generation process: In the ORC power generation process, the liquid working medium circulating in the whole process exchanges heat with the hot water in the first heat medium storage tank 17 in the preheater 29 and the second evaporator 30, and then enters the second air turbine 31 to do work, driving the generator 36 to generate electricity, and the electricity generated by the generator 36 is connected to the power grid 21 or used for the rotation of the hydrogen compressor in the hydrogen liquefaction subsystem. The exhaust steam after doing work enters the first condenser 32 from the second air turbine 31, and is converted into liquid after exchanging heat with the cold energy from the vaporization process in the LNG subsystem (that is, the liquid natural gas in the LNG storage tank 25 is converted into gaseous natural gas after passing through the LNG pump 26), and is pressurized by the fifth cold medium pump 33, and then enters the subsequent cycle, that is, from the preheater 29 to the second evaporator 30, the second evaporator 30 enters the second air turbine 31 to do work, and after doing work, the exhaust steam enters the first condenser 32, and after exchanging heat, it is pumped into the preheater 29 by the fifth cold medium pump 33, and continues to circulate from the preheater 29 to the second evaporator 30, and so on.

[0055] The hydrogen liquefaction process: after the hydrogen in the first hydrogen storage tank 48 is compressed by the second compressor 37, it exchanges heat with the first heat medium storage tank 17 and the second cold medium storage tank 18 of the heat storage subsystem in the second cooler 38, and the temperature is reduced. The heat energy after the exchange is stored in the first heat medium storage tank 17, and the cold energy required for the exchange comes from the second cold medium storage tank 18. The hydrogen after the heat exchange enters the hydrogen precooling device 39 for cooling. The cold energy required by the hydrogen precooling device 39 comes from the second cold storage medium storage tank 14 of the liquefaction subsystem. The hydrogen after the cooling enters the hydrogen liquefaction device 47 for liquefaction, and the liquefied liquid hydrogen is stored in the liquid hydrogen storage tank 40. The second compressor 37 is driven by the second motor 42, and the coupling with the heat energy and cold energy of the heat storage and exchange subsystem is controlled by controlling the sixth cold medium pump 44 and the eighth switch valve 45, and the coupling with the cold energy in the second cold storage medium storage tank 14 is controlled by controlling the seventh switch valve 41.

[0056] The energy utilization switching process between the different subsystems is controlled by a switch valve.

[0057] During off-peak hours or when there is wind or solar power abandonment, the liquefied compressed air energy storage process is started, and the gaseous air is converted into liquid air and stored in the liquid air storage tank. During the liquid compressed air energy storage process, the utilization of the cold energy of the LNG subsystem is controlled by the third switch valve 27 and the fourth switch valve 28. The selection of cold energy during the LNG vaporization process depends on whether the cold energy in the second cold storage medium storage tank 14 is sufficient. If it is sufficient, the fourth switch valve 28 is closed and the third switch valve 27 is opened; otherwise, the cold energy during the LNG vaporization process is utilized by opening the fourth switch valve 28 and closing the third switch valve 27.

[0058] During the peak period of electricity consumption, the energy release process of liquefied compressed air is started. During the energy release process, the heating process of the air heater 7 is controlled by the first switch valve 22 and the second switch valve 23. If the heat energy in the first heat medium storage tank 17 is sufficient, the first switch valve 22 is closed and the second switch valve 23 is opened. If the heat energy is insufficient, the first switch valve 22 is opened and the second switch valve 23 is closed. The air entering the air turbine is heated by the air heater 7. The high-temperature and high-pressure air drives the first generator 8 to generate electricity and is connected to the power grid 21.

[0059] At the same time, during the peak period of electricity consumption, the electric energy required by the second motor 42 of the hydrogen liquefaction subsystem comes from the ORC power generation process, realizing self-generation and self-use of electric energy. During the ORC power generation process, the cooling of the working fluid of the ORC power generation subsystem is controlled by the fifth switch valve 34 and the sixth switch valve 35. The cooling of the working fluid is achieved by opening the sixth switch valve 35 and closing the fifth switch valve 34, and the working fluid is condensed into a liquid state. Through the coupling of the ORC process and the LNG vaporization process, the utilization of cold energy in the LNG vaporization process is realized.

[0060] The utilization of heat energy and cold energy of the hydrogen liquefaction subsystem is controlled by the seventh switch valve 41 and the eighth switch valve 45. The utilization of cold energy is achieved by opening the seventh switch valve 41, and the utilization of heat energy is achieved by opening the eighth switch valve 45.

[0061] The above description shows and describes several preferred embodiments of the present invention, but as mentioned above, it should be understood that the present invention is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the application concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art shall not depart from the spirit and scope of the present invention, and shall be within the scope of protection of the claims attached to the present invention.

Claims

1. An advanced liquefied air energy storage system that couples multiple types of cold, hot and electric energy, characterized by: The system includes: a compressor subsystem, a liquefaction subsystem, an expander subsystem, a heat storage subsystem and an external energy subsystem; Wherein, the compressor subsystem is connected to the liquefaction subsystem; The liquefaction subsystem is simultaneously connected to the expander subsystem; The compressor subsystem is bidirectionally connected to the heat storage subsystem to achieve the transmission of heat energy or cold energy; The expander subsystem is bidirectionally connected to the heat storage subsystem to achieve the transmission of cold energy or heat energy; The external energy subsystem is bidirectionally connected to the heat storage subsystem to achieve energy exchange of external heat energy or cold energy.

2. The advanced liquefied air energy storage system according to claim 1, characterized in that: The external energy subsystem includes a liquefied natural gas (LNG) subsystem, an organic Rankine cycle (ORC) power generation subsystem, and a hydrogen liquefaction subsystem.

3. The advanced liquefied air energy storage system according to claim 1 or 2, characterized in that: The compressor subsystem includes a first compressor, an air filter, a first motor and a first cooler. The air filter is connected to the first compressor, and the first compressor is connected to the first cooler and the first motor at the same time.

4. The advanced liquefied air energy storage system according to claim 3, characterized in that: The expander subsystem includes a first air turbine, a first regenerator and an air heater connected in sequence.

5. The advanced liquefied air energy storage system according to claim 3, characterized in that: The liquefaction subsystem includes multiple energy flow heat exchangers, a throttle valve, a gas-liquid separator, a liquefied air storage tank, a first evaporator, a second cold storage medium pump, a first cold storage medium storage tank and a second cold storage medium storage tank. The multiple energy flow heat exchangers are connected to the first cooler and are connected to the gas-liquid separator through the throttle valve. The multiple energy flow heat exchangers are also connected to the first cold storage medium storage tank and the second cold storage medium storage tank. The gas-liquid separator is connected to the liquid air storage tank, and the liquid air storage tank is connected to the first evaporator. The first evaporator is also connected to the first cold storage medium storage tank and the second cold storage medium tank through the second cold storage medium pump.

6. The advanced liquefied air energy storage system according to claim 4, characterized in that: The ORC power generation subsystem includes a preheater, a second evaporator, a second air turbine, a first condenser, a fifth cold medium pump and a second generator. The preheater is connected to the second evaporator, the second evaporator is connected to the second air turbine, the second air turbine is connected to the first condenser, the second air turbine is also connected to the second generator, and the first condenser is connected to the fifth cold medium pump.

7. The advanced liquefied air energy storage system according to claim 6, characterized in that: The LNG subsystem includes an LNG storage tank, an LNG pump, a third switch valve, a fourth switch valve, a fifth switch valve, a sixth switch valve and a gaseous natural gas user. The LNG storage tank is connected to the LNG pump, the LNG pump is connected to the first condenser through the third switch valve and the sixth switch valve, the LNG pump is connected to the multiple energy flow heat exchangers through the fourth switch valve, and the multiple energy flow heat exchangers are connected to the gaseous natural gas user through the fifth switch valve.

8. The advanced liquefied air energy storage system according to claim 6, characterized in that: The hydrogen liquefaction subsystem includes a second compressor, a second cooler, a hydrogen precooling device, a liquid hydrogen storage tank, a second motor and an eighth switch valve. The second compressor is connected to the second cooler, and the second compressor is also connected to the second motor. The second cooler is connected to the hydrogen precooling device, and the hydrogen precooling device is connected to the liquid hydrogen storage tank.

9. The advanced liquefied air energy storage system according to claim 8, characterized in that: The heat storage subsystem includes a first heat medium storage tank, a first cold medium storage tank, a third heat medium pump, a fourth cold medium pump, a sixth cold medium pump, and a sixth heat medium pump. The second cold medium storage tank is connected to the first cooler and the second evaporator through the fourth cold medium pump, and is connected to the second cooler and the first regenerator through the sixth cold medium pump. The first heat medium storage tank is connected to the first cooler, connected to the first regenerator through the third heat medium pump, connected to the preheater through the sixth heat medium pump, and connected to the second cooler through the eighth switch valve.

10. A method for operating an advanced liquefied air energy storage system that couples multiple types of cold, hot, and electric energy, characterized in that: The method is implemented using the system described in any one of claims 1 to 9, and includes a liquefied compressed air energy storage process, a liquefied compressed air energy storage and release process, an LNG vaporization process, an ORC power generation process, a hydrogen liquefaction process, and a switching process between different processes.

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