A compressed gas energy storage device

Abstract

The application provides a compressed gas energy storage device, which comprises a heat storage subsystem, a cold storage subsystem and a cold and heat energy generation subsystem; the heat storage subsystem comprises a first motor, a first compressor and a heat storage device, the outlet of the first compressor is connected with the inlet of the heat storage device, and the first motor is electrically connected with the first compressor; the cold storage subsystem comprises a cold storage device; the cold and heat energy generation subsystem comprises a second compressor and a first expander which are coaxially arranged; a first three-way valve and a second three-way valve are arranged on a pipeline; the first passage of the first three-way valve is connected with the outlet pipeline of the cold storage device, the second passage is connected with the inlet pipeline of the second compressor, and the third passage is connected with the inlet pipeline of the cold storage device; the fourth passage of the second three-way valve is connected with the outlet pipeline of the heat storage device, the fifth passage is connected with the inlet pipeline of the first expander, the sixth passage is connected with the outlet pipeline of the first compressor, and the second compressor is connected with the inlet pipeline of the heat storage device through a pipeline.

Description

Technical Field

[0001] This application relates to the field of new energy, and in particular to a compressed gas energy storage device. Background Technology

[0002] Conventional compressed gas energy storage stores thermal energy in a storage tank during charging and uses this thermal energy to preheat the high-pressure gas during discharging to improve system efficiency. A dual-tank thermal storage system is typically required. While packed bed thermal storage systems are relatively inexpensive, using inexpensive rock particles as the storage medium, they contain a thermocline, causing temperature fluctuations at the outlet during heat storage and release. This results in poor system stability during the charging and discharging process of compressed gas energy storage. Utility Model Content

[0003] This application provides a compressed gas energy storage device to solve the problem of low testing efficiency of traditional compressed gas energy storage devices.

[0004] To address the aforementioned technical problems, this application provides a compressed gas energy storage device, comprising: a thermal energy storage subsystem, a cold energy storage subsystem, and a thermal energy generation system.

[0005] The thermal storage subsystem includes a first motor, a first compressor, and a thermal storage device. The outlet of the first compressor is connected to the inlet of the thermal storage device, and the first motor is electrically connected to the first compressor.

[0006] The cold storage subsystem includes a cold storage unit, and the cold and heat energy generation electronic system includes a second compressor and a first expander arranged coaxially, with a first three-way valve and a second three-way valve installed on the pipeline;

[0007] The first passage of the first three-way valve is connected to the outlet pipe of the cold storage tank, the second passage is connected to the inlet pipe of the second compressor, and the third passage is connected to the inlet pipe of the cold storage tank.

[0008] The fourth passage of the second three-way valve is connected to the outlet pipe of the heat storage tank, the fifth passage is connected to the inlet pipe of the first expander, the sixth passage is connected to the outlet pipe of the first compressor, and the second compressor is connected to the inlet pipe of the heat storage tank through a pipe.

[0009] One of the above technical solutions has the following advantages or beneficial effects:

[0010] In this embodiment, the system includes a thermal storage subsystem, a cold storage subsystem, and a thermal energy generation system. The thermal storage subsystem includes a first motor, a first compressor, and a heat storage tank. The outlet of the first compressor is connected to the inlet of the heat storage tank, and the first motor is electrically connected to the first compressor. The cold storage subsystem includes a cold storage tank. The thermal energy generation system includes a second compressor and a first expander coaxially arranged, with a first three-way valve and a second three-way valve installed on the pipeline. The first three-way valve has a first passage connected to the outlet pipeline of the cold storage tank, a second passage connected to the inlet pipeline of the second compressor, and a third passage connected to the inlet pipeline of the cold storage tank. The second three-way valve has a fourth passage connected to the outlet pipeline of the heat storage tank, a fifth passage connected to the inlet pipeline of the first expander, and a sixth passage connected to the outlet pipeline of the first compressor. The second compressor is connected to the inlet pipeline of the heat storage tank via a pipeline. This embodiment utilizes the first compressor in the thermal storage subsystem to compress and pump the gaseous working fluid to a higher temperature, thereby extracting and storing the heat energy generated during the compressed gas energy storage and charging process in the heat storage tank, without requiring the use of expensive molten salt thermal storage methods, thus reducing costs. Simultaneously, the cold energy released by the expanding gas in the discharge system is stored in the cold storage subsystem, achieving cold energy recovery and utilization, thus avoiding energy waste. The second compressor and first expander, coaxially arranged in the thermal energy generation system, convert the stored high-grade thermal and cold energy into electrical energy, providing flexible power output. Furthermore, the first and second three-way valves on the pipeline, along with their connections, allow for fluid path switching between different modes such as thermal storage, cold storage, and power generation, ensuring continuous and stable charging and discharging of the compressed gas energy storage system and improving the stability and flexibility of the compressed gas energy storage device during charging and discharging. Attached Figure Description

[0011] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments of this application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0012] Figure 1 This is one of the structural schematic diagrams of the compressed gas energy storage device provided in the embodiments of this application;

[0013] Figure 2 This is a second schematic diagram of the compressed gas energy storage device provided in the embodiments of this application;

[0014] Figure 3 This is a schematic diagram of a three-way valve structure provided in one embodiment of this application. Detailed Implementation

[0015] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0016] like Figure 1 As shown, this utility model embodiment provides a compressed gas energy storage device, such as... Figure 1 As shown, it includes:

[0017] Thermal energy storage subsystem, cold energy storage subsystem, and thermal energy generation subsystem;

[0018] The thermal storage subsystem includes a first motor 23, a first compressor 12, and a thermal storage device 13. The outlet of the first compressor 12 is connected to the inlet of the thermal storage device 13, and the first motor 23 is electrically connected to the first compressor 12.

[0019] The cold storage subsystem includes a cold storage unit 14, and the cold and heat energy generation electronic system includes a second compressor 16 and a first expander 17 arranged coaxially. A first three-way valve 21 and a second three-way valve 19 are provided on the pipeline.

[0020] The first passage of the first three-way valve 21 is connected to the outlet pipe of the cold storage tank 14, the second passage is connected to the inlet pipe of the second compressor 16, and the third passage is connected to the inlet pipe of the cold storage tank 14.

[0021] The fourth passage of the second three-way valve 19 is connected to the outlet pipe of the heat storage tank 13, the fifth passage is connected to the inlet pipe of the first expander 17, the sixth passage is connected to the outlet pipe of the first compressor 12, and the second compressor 16 is connected to the inlet pipe of the heat storage tank 13 through a pipe.

[0022] In the embodiments of this application, Figure 1 To illustrate the structural form, the aforementioned thermal energy storage subsystem is used to store the heat energy generated during the compressed gas energy storage process. It includes a first motor 23, a first compressor 12, and a thermal energy storage unit 13, and can be connected to the charging subsystem via a high-temperature heat exchanger 3. The aforementioned cold energy storage subsystem can be used to store the cold energy released by the expanded air. It includes a cold energy storage unit 14 and a circulating fan 15, and can be connected to the power generation system via a low-temperature heat exchanger 8. The aforementioned thermal energy power generation system can generate electricity using the energy stored in the thermal energy storage unit 13 and the cold energy storage unit 14. It may include a coaxially arranged second compressor 16 and a first expander 17, and the energy flow path can be switched via a three-way valve.

[0023] The above three-way valve can be referenced. Figure 3 A valve with three passages (A, B, C) can, in some optional embodiments, switch the connection state via an electric actuator to achieve fluid path control in modes such as heat storage, cold storage, and power generation.

[0024] The outlet of the first compressor 12 is connected to the inlet of the heat storage tank 13, and the first motor 23 is electrically connected to the first compressor 12. The specific number and model of the compressors are not specifically limited in this application. For example, the first compressor 12 can be a single-stage centrifugal compressor, driven by the first motor 23, to compress the gaseous working fluid flowing out of the second passage of the high-temperature heat exchanger 3 to a higher temperature and send it into the heat storage tank 13; or it can be a multi-stage series compressor. The choice of the heat storage tank 13 is also not specifically limited in this application. It can be a vertical packed bed structure, filled with granite particles, which can achieve thermal energy storage through bottom air intake and top air outlet; or it can be filled with phase change material microcapsules, such as paraffin-based phase change materials, with the microcapsule shell being a polymer material, achieving latent heat storage through a phase change process and increasing the heat storage density. In some optional embodiments, the first motor 23 can also be a variable frequency motor, which can dynamically adjust the compressor speed according to the inlet temperature of the heat storage tank 13. The heat storage unit 13 can adopt a horizontal structure and can be equipped with multiple layers of metal partitions inside. The partitions can have flow guide holes to allow high-temperature gas to flow evenly through the packed bed and reduce the influence of the inclined temperature layer.

[0025] Regarding the selection of the aforementioned cold storage unit 14, this application embodiment is not limited. A vertical packed bed can be used, filled with irregularly shaped basalt particles. A gas distributor can be installed at the bottom to ensure that the cryogenic working fluid flows uniformly through the packed bed. The aforementioned circulating fan 15 can be an axial flow fan, installed on the pipeline between the cold storage unit 14 and the cryogenic heat exchanger 8, driving the working fluid to circulate at a preset flow rate. The aforementioned cold storage unit 14 can also adopt a spiral tube structure, with the cryogenic working fluid flowing through the internal coil. The outside of the coil can be filled with metallic aluminum particles, utilizing the high thermal conductivity of metal to improve the cold energy transfer efficiency. The circulating fan 15 can also be a centrifugal fan. In some optional embodiments, a soundproof cover can be equipped to reduce noise. A filter can be installed in the inlet pipe of the circulating fan 15 to prevent packed bed particles from entering the circulation loop. In some optional embodiments, the aforementioned cold storage unit 14 and the cryogenic heat exchanger 8 can be connected by a flexible corrugated pipe. The corrugated pipe can have a built-in pressure compensation device to absorb fluid impact vibration during fan start-up and shutdown. The motor of the circulating fan 15 can also be an explosion-proof motor, which is suitable for cold energy recovery scenarios of flammable and explosive working fluids.

[0026] The aforementioned thermal energy generation system includes a second compressor 16 and a first expander 17 coaxially arranged, with a first three-way valve 21 and a second three-way valve 19 installed on the pipeline. The second compressor 16 and the first expander 17 can be coaxially connected via a rigid coupling, sharing the same drive shaft to drive the generator 18 to generate electricity. The first three-way valve 21 can be an electric three-way ball valve, which can rotate a certain angle after being energized to switch the passage. The working fluid at the outlet of the cold storage tank 14 can flow into the inlet of the second compressor 16 (the B passage of the first three-way valve 21) through the first passage (A) of the first three-way valve 21. The low-temperature cold energy, after passing through the low-temperature heat exchanger, can enter the cold storage tank 14 through the third passage (C) of the first three-way valve 21. The ambient temperature working fluid after power generation can return to the inlet of the cold storage tank 14 through pipelines or valves. In some optional embodiments, the second compressor 16 and the first expander 17 can also be coaxially connected via a gearbox. The gearbox can have a built-in speed change mechanism to adjust the compression ratio and expansion ratio according to the outlet temperature of the heat storage tank 13. The second three-way valve 19 can be a pneumatic three-way valve, which uses compressed gas to drive a piston to switch the passage, suitable for power generation scenarios requiring rapid start-up and shutdown. The aforementioned thermal power generation system can also be equipped with multiple parallel-connected second compressors 16 and first expanders 17, with the number of operating units adjustable according to grid load requirements. The aforementioned three-way valve can be equipped with a position feedback sensor to monitor the valve opening in real time and transmit the signal to the controller for automated control.

[0027] The first passage of the aforementioned first three-way valve 21 is connected to the outlet pipe of the cold storage tank 14, the second passage is connected to the inlet of the second compressor 16, and the third passage is connected to the inlet of the cold storage tank 14; the fourth passage (passage A) of the second three-way valve 19 is connected to the outlet pipe of the heat storage tank 13, the fifth passage (passage B) of the second three-way valve 19 is connected to the inlet of the first expander 17, and the sixth passage (passage C) of the second three-way valve 19 is connected to the outlet of the first compressor 12. Figure 2 As shown, when the power grid demand increases, the cold and heat energy generation system is activated, connecting the AB passage of the first three-way valve 21. The working fluid path is as follows: the low-temperature gas flows from the outlet of the cold storage tank 14 to the A and B passages of the first three-way valve 21, then to the inlet of the second compressor 16, where it is compressed to normal temperature and high pressure. It then enters the heat storage tank 13 to absorb heat energy to a high temperature and high pressure state, and finally enters the first expander 17 through the AB passage of the second three-way valve 19 to expand and perform work. The work done by the first expander 17 is higher than the power consumption of the second compressor 16, and the shaft power can be transferred to the generator 18 to generate electricity.

[0028] In the discharge process mode of the compressed air energy storage system, the AC passage of the first three-way valve 21 can be connected. The working fluid path is as follows: after the heat exchange working fluid in the cold storage subsystem absorbs cold energy, it can flow into the cold storage unit 14 through the CA passage of the first three-way valve 21.

[0029] In the charging mode of the compressed air energy storage system, the aforementioned second three-way valve 19 can connect the fourth and sixth passages (the AC passage of the second three-way valve 19). High-temperature gas flows into the heat storage tank 13 through the CA passage of the second three-way valve 19 to exchange heat with the solid heat storage material therein, thus storing thermal energy. After releasing thermal energy, the gaseous working fluid can flow out from the valve or pipe and return to the seventh passage of the heat exchanger to continue absorbing thermal energy, forming a cycle from the heat storage tank 13 to the first compressor 12. In some optional embodiments, the aforementioned three-way valve can be made of stainless steel, and pressure sensors can be installed on the valve's inlet and outlet pipes. When the pressure difference exceeds a set threshold, an alarm can be triggered, and the three-way valve can be switched to the backup passage. The aforementioned three-way valve can be switched by a pneumatic actuator, an electric actuator, or other types of actuators. This application does not specifically limit the implementation of these mechanisms.

[0030] In some alternative implementations, the second three-way valve 19 can have an isolation effect. During the power generation stage, the fourth passage (passage A) and the fifth passage (passage B) of the second three-way valve 19 are connected, and the sixth passage (passage C, which leads to the outlet of the first compressor 12) is closed or restricted. This ensures that the high-temperature and high-pressure gas released by the heat storage device flows only to the expander, rather than flowing back to the outlet of the first compressor 12 (the high-temperature gas path during the energy storage stage), thus preventing heat energy from returning to the energy storage loop with the gas. During the power generation stage, since the three-way valve switches to the power generation path, the heat storage device 13 is directly connected to the first expander 17, and the compressor loop (first compressor 12) during the energy storage stage is isolated by the valve, so that heat energy flows unidirectionally only in the power generation loop.

[0031] Furthermore, while the first expander 17 is working to drive the generator, it also coaxially drives the second compressor 16 to operate. The function of the second compressor is to heat and pressurize the low-temperature gas flowing out of the accumulator 14.

[0032] In this embodiment, the first compressor 12 in the thermal storage subsystem compresses the gaseous working fluid to a higher temperature, enabling the extraction and storage of heat energy generated during the compressed gas energy storage charging process in the thermal storage unit 13. This eliminates the need for expensive molten salt thermal storage, reducing costs. Simultaneously, the cold energy released by the expanding gas in the discharging system is stored in the cold storage subsystem, achieving cold energy recovery and avoiding energy waste. The second compressor 16 and the first expander 17, coaxially arranged in the thermal and cold energy discharging system, convert the stored high-grade thermal and cold energy into electrical energy, providing flexible power output. Furthermore, the first three-way valve 21 and the second three-way valve 19 on the pipeline, along with their connections, allow for fluid path switching between different modes such as thermal storage, cold storage, and power generation, ensuring continuous and stable charging and discharging of the compressed gas energy storage system and improving the stability and flexibility of the compressed gas energy storage device during charging and discharging.

[0033] Optionally, the device further includes a gas storage system 6, a charging subsystem, and a discharge system. The charging subsystem includes a third compressor 2 and a high-temperature heat exchanger 3 connected to each other. The high-temperature heat exchanger 3 includes a seventh passage and an eighth passage. The outlet of the seventh passage is connected to the first compressor 12 via a pipe. The gas storage system 6 is connected to the outlet of the eighth passage. The discharge system includes a second expander 7 and a low-temperature heat exchanger 8 connected to each other. The low-temperature heat exchanger 8 has a ninth passage and a tenth passage. The outlet of the ninth passage is connected to the outside. The outlet of the tenth passage is connected to the cold storage unit 14. The outlet of the gas storage system 6 is connected to the inlet of the second expander 7 via a pipe.

[0034] In this embodiment, such as Figure 2 As shown, the gas storage system 6 can be used to store the ambient temperature high-pressure gas output from the charging subsystem. It can be an underground gas storage facility, such as a depleted oil and gas reservoir or a salt cavern, or a surface high-pressure storage tank, featuring large capacity and low leakage. The charging subsystem can compress the gas and store pressure energy using a compressor, while simultaneously transferring the heat generated by compression to the thermal storage subsystem via a high-temperature heat exchanger 3. This subsystem includes a third compressor 2 and a high-temperature heat exchanger 3. The discharge system can expand the high-pressure gas in the gas storage system 6 using an expander to generate electricity, while simultaneously transferring the cold energy generated by expansion to the cold storage subsystem via a low-temperature heat exchanger 8. This subsystem includes a second expander 7 and a low-temperature heat exchanger 8. The eighth passage can be understood as the channel in the high-temperature heat exchanger 3 for the flow of compressed gas, where the compressed gas releases heat before entering the gas storage system 6. The seventh passage can be understood as the channel in the high-temperature heat exchanger 3 for the flow of the thermal storage medium, where it absorbs the heat released by the compressed gas before entering the thermal storage subsystem. The aforementioned ninth passage can be understood as the channel in the cryogenic heat exchanger 8 used for the flow of expanding gas, where the expanding gas releases cold energy and is then discharged into the atmosphere. The aforementioned tenth passage can be understood as the channel in the cryogenic heat exchanger 8 used for the flow of the cold storage working fluid, which absorbs the cold energy released by the expanding gas and then enters the cold storage subsystem.

[0035] In some optional embodiments, the third compressor 2 can be multiple centrifugal compressors connected in series, or multiple third compressors 2 connected in parallel. The number of operating compressors can be dynamically adjusted according to the power grid load. It can also be a single-stage axial flow compressor and can be equipped with an intercooler. This application does not specifically limit the embodiments in this regard.

[0036] In some optional embodiments, a buffer tank is installed between the gas storage system 6 and the charging subsystem. The inlet of the buffer tank is connected to the outlet of the eighth passage, and the outlet is connected to the inlet of the gas storage tank. A pressure sensor is installed inside the buffer tank. When the output pressure of the charging subsystem fluctuates, the buffer tank volume is adjusted to stabilize the inlet pressure of the gas storage tank. The gas storage system 6 can be an underground salt cavern gas storage tank. The outlet pipe of the eighth passage is connected to the inlet of the gas storage tank through an underground gas transmission pipeline. The inner wall of the pipeline can be coated with an anti-corrosion coating. The gas storage system 6 can also be a surface metal storage tank, which can adopt a double-layer pressure vessel structure. The outer layer can be set as an atmospheric pressure insulation layer, for example, by filling with polyurethane foam. A dryer can also be installed at the outlet of the eighth passage to remove moisture from the compressed gas and prevent corrosion inside the storage tank.

[0037] The aforementioned second expander 7 can be two axial-flow expanders connected in series. After the high-pressure gas flows out, it first expands through the first expander and then expands to atmospheric pressure through the second expander. The cryogenic heat exchanger 8 can be a dual-pass counter-flow spiral plate structure. The ninth pass introduces the cryogenic expansion gas, and the tenth pass introduces the cold storage medium. The cold energy is transferred to the cold storage medium through the pipe wall, and the expansion gas is finally discharged into the atmosphere from the ninth pass. The aforementioned second expander 7 can also be a single-stage centripetal turbine expander, which can be equipped with a generator to directly drive power generation. The cryogenic heat exchanger 8 adopts a coiled tube structure. The cold storage medium in the tenth pass flows counter-currently through the expansion gas in the ninth pass at a certain flow rate. After the cold storage medium is cooled at the outlet, it flows into the cold storage tank 14.

[0038] Of course, an integrated compressor and heat exchanger structure can be used to replace the above technical solution. Specifically, the third compressor 2 and the high-temperature heat exchanger 3 of the charging subsystem can be integrated. The outlet of the third compressor 2 can be directly connected to the seventh passage inlet of the high-temperature heat exchanger 3, omitting the intermediate connecting pipe. The eighth passage outlet of the high-temperature heat exchanger 3 can be connected to the inlet of the gas storage system 6 through a built-in guide channel to reduce fluid resistance. Alternatively, in some optional embodiments, a modular compressor-heat exchanger unit can be used. For example, multiple third compressors 2 and high-temperature heat exchangers 3 can be grouped and connected in parallel. The outlet of each group of compressors is connected to the seventh passage of the corresponding high-temperature heat exchanger 3, and the outlets of the eighth passages of each group are combined to the gas storage system 6, which allows for flexible adjustment of the system charging power.

[0039] In this embodiment, the connection between the third compressor 2 and the high-temperature heat exchanger 3 in the charging subsystem enables the transfer of heat energy from the compressed gas to the heat storage subsystem during charging and the storage of room-temperature high-pressure gas in the gas storage system 6. The connection between the gas storage system 6 and the discharge system enables the high-pressure gas to expand and perform work via the second expander 7 during discharge and the transfer of cold energy to the cold storage subsystem. The ninth and tenth pathways of the low-temperature heat exchanger 8 enable the release and venting of the expanded gas and the absorption and storage of cold energy by the cold storage medium. The dual-path configuration of the high-temperature heat exchanger 3 and the low-temperature heat exchanger 8 decouples heat energy from pressure energy during the charging process and decouples cold energy from pressure energy during the discharge process, ensuring that the compressed gas energy storage system always operates under its design conditions and guarantees continuous and stable charging and discharging. Simultaneously, the stored heat energy can be flexibly converted into electrical energy for output through the heat and cold energy generation system.

[0040] Optionally, the discharge system includes at least one second expander 7 connected in series.

[0041] In this embodiment, the aforementioned at least one expander connected in series can be understood as multiple expanders connected sequentially in a pipeline. The gas flows through each expander in sequence, with the inlet pressure and outlet temperature of each expander decreasing progressively, thus achieving multi-stage expansion and work. Through multi-stage series expansion, the high-pressure gas releases pressure energy in stages. After each expansion stage, the gas is cooled by a cryogenic heat exchanger 8, avoiding instability in the working fluid state caused by excessive temperature drop during single-stage expansion, while also improving cold energy recovery efficiency. Multi-stage expansion allows the expanders to operate within a more efficient pressure ratio range, reducing mechanical losses and adapting to pressure fluctuations at the outlet of the gas storage system 6.

[0042] Regarding the specific form of the second expander 7 connected in series, this application embodiment does not make specific limitations. Two axial flow expanders can be connected in series, and the two-stage expansion can release the pressure in stages; or three centripetal turbine expanders can be connected in series, and the last-stage expander can be flexibly started and stopped according to the capacity of the cold storage 14 to improve the system's adjustment capability.

[0043] Of course, a variable-stage series expander can also be used. For example, two expanders are connected in parallel via an electric three-way valve and operate in series under normal conditions (path AB). When the pressure of the gas storage system 6 is lower than the preset threshold, the three-way valve switches to bypass mode (path AC) and only the second-stage expander operates. The number of expansion stages can be dynamically adjusted to avoid the efficiency decay of multi-stage expansion under low-pressure conditions. Variable frequency control reduces mechanical shock and extends equipment life.

[0044] Optionally, the charging subsystem includes at least one third compressor 2 connected in series.

[0045] In this embodiment, the aforementioned at least one third compressor 2 connected in series can be understood as multiple compressors connected sequentially in a pipeline. Air flows through each stage compressor in sequence, and the inlet pressure of each stage compressor increases step by step while the outlet temperature remains unchanged, forming a multi-stage compression process of "compression to cooling; recompression to recooling".

[0046] In this embodiment, multi-stage series compression reduces the compression ratio of a single stage, which can reduce the difficulty of equipment development to some extent. The stages can be cooled by a high-temperature heat exchanger 3, allowing the compression heat to be fully recovered to the heat storage subsystem, thus improving thermal energy utilization and ensuring that the gas entering the gas storage system 6 is at room temperature and high pressure.

[0047] The specific form of the series connection of the compressors is not limited in the embodiments of this application. In some optional embodiments, a variable-stage series compressor can be used. For example, the basic configuration is two compressors connected in series. When a higher pressure is required, a third compressor can be connected via an electric valve to form a three-stage compression process. A pressure sensor can be installed at the inlet of each compressor stage. When the outlet pressure of the first-stage compressor exceeds a first threshold, the second-stage compressor is automatically started; when it exceeds a second threshold, the third-stage compressor is started. The number of compression stages can be dynamically adjusted to adapt to different gas storage pressure requirements. Redundancy design can also improve system reliability. When a single compressor fails, it can switch to a fewer-stage compression mode.

[0048] Optionally, the outlet of the heat storage tank 13 forms a circulation pipeline with the seventh passage inlet of the high-temperature heat exchanger 3 through the second three-way valve 19 and the third three-way valve 20;

[0049] The sixth passage inlet of the second three-way valve 19 is connected to the outlet of the first compressor 12 through a pipe, the inlet of the first compressor 12 is connected to the seventh passage through a pipe, and the fourth passage of the second three-way valve 19 is connected to the inlet of the heat storage tank 13 through a pipe.

[0050] The outlet of the heat storage tank 13 is connected to the eleventh passage (C passage) of the third three-way valve 20 through a pipe, the twelfth passage (A passage) of the third three-way valve 20 is connected to the inlet of the seventh passage through a pipe, and the second compressor 16 is connected to the heat storage tank 13 through the thirteenth passage (B passage) of the third three-way valve 20.

[0051] In some alternative embodiments, when the heat storage circuit is a closed circuit, at least one pressure relief device can be provided in the twelfth passage of the third three-way valve 20, that is, the section of pipeline from the third three-way valve 20 to the inlet of the heat exchanger 3, so that the pressure of the heat storage circuit can be stabilized, that is, the inlet pressure of the first compressor 12 is constant.

[0052] In this embodiment, the outlet circulation pipe of the aforementioned heat storage device 13 is a pipe network connecting the heat storage device 13, the second three-way valve 19, the third three-way valve 20 and the high-temperature heat exchanger 3, which is used to realize the thermal energy circulation storage of the heat storage subsystem or to supply energy to the cold and hot energy generation system.

[0053] The aforementioned second three-way valve 19 is a three-way valve located between the outlet of the heat storage tank 13 and the high-temperature heat exchanger 3, used to switch the connection between the heat storage tank 13 and the first compressor 12 or the high-temperature heat exchanger 3. The aforementioned third three-way valve 20 can be used to connect the outlet of the heat storage tank 13, the inlet of the high-temperature heat exchanger 3, and the second compressor 16 of the cooling and heating energy generation system.

[0054] In this embodiment, by switching the passages of the second three-way valve 19 and the third three-way valve 20, a thermal energy circulation pipeline is formed between the thermal storage tank 13 and the high-temperature heat exchanger 3. This enables the thermal storage subsystem to continuously recover and store the compressed heat in thermal storage mode, and to supply thermal energy to the thermal power generation system in cold and hot energy power generation mode. This improves the thermal energy utilization rate and supports the flexible operation of the system in multiple modes.

[0055] Furthermore, whether or not a loop structure is used does not affect the implementation of the basic functions of the embodiments of this application.

[0056] Optionally, the cold storage subsystem includes a cold storage unit 14 and a circulating fan 15;

[0057] The outlet of the cold storage 14 forms a circulation pipe with the tenth passage inlet of the low-temperature heat exchanger 8 through the first three-way valve 21 and the fourth three-way valve 22.

[0058] The tenth passage inlet is connected to the outlet of the circulating fan 15 through a pipe, the inlet of the circulating fan 15 is connected to the fourteenth passage of the fourth three-way valve 22 through a pipe, the fifteenth passage of the fourth three-way valve 22 is connected to the outlet of the cold storage 14 through a pipe, and the sixteenth passage of the fourth three-way valve 22 is connected to the first expander 17 through a pipe.

[0059] The inlet of the cold storage 14 is connected to the first passage of the first three-way valve 21 via a pipe, and the third passage of the first three-way valve 21 is connected to the tenth passage outlet of the low-temperature heat exchanger 8 via a pipe.

[0060] The aforementioned circulating fan 15 drives the cold storage medium to circulate between the cold storage tank 14 and the low-temperature heat exchanger 8. The aforementioned first three-way valve 21 is a three-way valve located between the inlet of the cold storage tank 14 and the low-temperature heat exchanger 8, used to switch the flow direction of the cold storage medium. The aforementioned fourth three-way valve 22 is a three-way valve located between the outlet of the cold storage tank 14 and the circulating fan 15, working in conjunction with the first three-way valve 21 to achieve circulation path switching. The aforementioned tenth passage can be understood as the channel for the cold storage medium to circulate in the low-temperature heat exchanger 8, used to absorb the cold energy released by the expanding air. In cold storage mode, the fourteenth and fifteenth passages of the fourth three-way valve 22 are connected, and the first and third passages of the first three-way valve 21 are connected; in power generation mode, the fifteenth and sixteenth passages of the fourth three-way valve 22 are connected, and the first and second passages of the first three-way valve 21 are connected, allowing the medium to flow to the cold and heat energy power generation system. For example, the path of the circulating fan 15 can be from the outlet of the circulating fan 15 to the inlet of the tenth passage of the low-temperature heat exchanger 8 to absorb cold energy; from the outlet of the tenth passage of the low-temperature heat exchanger 8 to the third passage of the first three-way valve 21 and then to the inlet of the cold storage 14 to store cold energy; and from the outlet of the cold storage 14 to the fifteenth passage of the fourth three-way valve 22 and then to the inlet of the circulating fan 15 to complete the circulation.

[0061] In this embodiment, the circulation pipeline formed by the cold storage tank 14, the circulating fan 15, the first three-way valve 21 and the fourth three-way valve 22 realizes the efficient recovery and storage of cold energy of the expanded air in the discharge system; by switching the three-way valve passage, the cold storage mode and the cold and heat power generation mode can be flexibly switched to improve the cold energy utilization rate; the circulating fan 15 drives the working fluid to flow continuously, ensuring the stability of cold energy transfer and enabling the compressed gas energy storage system to operate stably under the design conditions.

[0062] For example, during the charging process of the compressed air energy storage system, the third compressor 2 is driven to rotate, compressing the ambient temperature and pressure air to a medium-high temperature and high pressure state. Subsequently, the medium-high temperature gas working fluid flows into the seventh passage of the high-temperature heat exchanger 3, transferring heat energy to the heat storage subsystem. The ambient temperature and high pressure gas that has released its heat energy flows out from the eighth passage of the high-temperature heat exchanger 3 and is stored in the gas storage system 6.

[0063] The electric motor drives the first compressor 12 to pump the gas to a higher temperature. The high-temperature gas flows into the heat storage tank 13 through the CA passage of the second three-way valve 19 to exchange heat with the solid heat storage material therein and store the heat energy therein. After releasing the heat energy, the gas working medium flows out through the CA passage of the third three-way valve 20 and returns to the seventh passage of the heat exchanger 3 to continue to absorb heat energy.

[0064] The discharge process of the compressed air energy storage system: Room temperature high-pressure gas flows out from the gas storage system 6, sequentially into the second expander 7, the cryogenic heat exchanger 8, and the series-connected second expander 7 and cryogenic heat exchanger 8, where it expands, releases cold, expands again, and releases cold again before flowing into the atmosphere. After expansion, the room temperature high-pressure gas reaches a low-temperature state, and the low-temperature cold energy is transferred to the cold storage subsystem via the cryogenic heat exchanger 8.

[0065] The circulating fan 15 drives the heat exchange medium in the cold storage subsystem to flow into the tenth passage of the cold storage heat exchanger to absorb cold energy. It then flows into the cold storage 14 through the AB passage of the first three-way valve 21, and then flows out through the AC passage of the fourth three-way valve 22, repeating the cycle.

[0066] Cold and heat energy generation electronic system: When the power grid demand increases, the cold and heat energy generation electronic system is activated. It connects the AB passage of the second three-way valve 19, the BC passage of the third three-way valve 20, the AB passage of the first three-way valve 21, and the BC passage of the fourth three-way valve 22. The second compressor 16 and the first expander 17 are coaxially connected. Low-temperature gas flows out from the cold storage tank 14, flows into the second compressor 16 for compression to normal temperature and high pressure, then enters the heat storage tank 13 to absorb heat energy to a high temperature and high pressure state, and then enters the first expander 17 for expansion and work. The work done by the first expander 17 is higher than the power consumption of the second compressor 16, and the shaft power is transferred to the generator 18 to generate electricity.

[0067] Thermal and cold energy absorption and release: Thermal storage unit 13 and cold storage unit 14 can achieve flexible absorption and release of thermal and cold energy through parallel heat exchangers. This allows for the absorption and utilization of high-grade thermal energy such as solar thermal and industrial waste heat, the recovery of LNG cold energy, or coupling with an air separation system. When there is an external demand for thermal or cold energy, it can also flexibly release thermal or cold energy for industrial heating / cooling, residential heating / cooling supply, and other scenarios.

[0068] It should be noted that in some optional implementations, the discharge mode of the compressed air energy storage system can be carried out simultaneously with the power generation mode. That is, while the cold and hot energy power generation system is started and running, the room temperature high pressure gas can flow out from the gas storage system 6 and flow into the second expander 7, the low temperature heat exchanger 8, and the second expander 7 and the low temperature heat exchanger 8 connected in series to expand, release cold, expand, release cold, and then flow into the atmosphere.

[0069] In some alternative implementations, the power of the generator 18 can be adjusted. For example, the gas flow rate can be adjusted by a three-way valve to control the gas parameters entering the first expander 17 or to change the load of the second compressor, or by other means. This application does not specifically limit the implementation of this method.

[0070] Alternatively, a cold storage circulation system based on a two-way valve assembly and a distributor can be used. For example, the three-way valve in the above embodiment can be replaced by a two-way valve assembly and a distributor, working in conjunction with the circulating fan 15 to achieve cold energy recovery and mode switching. The specific structure is as follows:

[0071] In the cold storage mode: the circulating fan 15 drives the working fluid to flow through the low-temperature heat exchanger 8 to absorb cold energy, and then enters the cold storage tank 14 through the two-way valve V1 to store cold energy; the working fluid at the outlet of the cold storage tank 14 is divided into two paths by the distributor: one path flows directly back to the inlet of the circulating fan 15 through the two-way valve V2, and the other path regulates the flow through the two-way valve V3 to maintain the temperature of the cold storage tank 14.

[0072] In power generation mode: V1 and V2 are closed, and the connection valves of V3 and the cold and hot energy power generation system are opened. The working fluid at the outlet of the cold storage tank 14 is guided to the first expander 17 through the distributor to participate in the power generation cycle.

[0073] Optionally, the high-temperature heat exchanger 3 and the low-temperature heat exchanger 8 are dual-pass counter-flow pipe structures, with the seventh passage and the eighth passage having opposite flow directions, and the ninth passage and the tenth passage having opposite flow directions.

[0074] In this embodiment, the dual-pass counter-flow pipe structure can be understood as a heat exchanger containing two independent pipe passages, in which the two fluids flow in opposite directions and exchange heat through the pipe walls. The counter-flow layout maximizes the logarithmic mean temperature difference between the hot and cold fluids. In the high-temperature heat exchanger 3, the compressed air outlet temperature can approach the inlet temperature of the heat storage medium; in the low-temperature heat exchanger 8, the expansion air outlet temperature can approach the inlet temperature of the cold storage medium, reducing energy waste. Furthermore, the counter-flow design can reduce the heat exchanger volume, pipe length, and system complexity. The aforementioned counter-flow heat exchanger can be a shell-and-tube counter-flow high-temperature heat exchanger 3, a plate-fin counter-flow low-temperature heat exchanger 8, or a spiral plate counter-flow heat exchanger; this application does not specifically limit the implementation of this method.

[0075] Of course, using other high-temperature heat exchangers 3 and low-temperature heat exchangers 8 does not affect the realization of the basic functions of the embodiments of this application. Therefore, the implementation method of this application is not specifically limited.

[0076] Optionally, the first three-way valve 21, the second three-way valve 19, the third three-way valve 20, and the fourth three-way valve 22 are electric three-way valves, which switch the passage state through an electric actuator; the compressed gas energy storage device also includes a controller, which is electrically connected to the first three-way valve 21, the second three-way valve 19, the third three-way valve 20, and the fourth three-way valve 22.

[0077] In this embodiment, the electric three-way valve can be understood as a valve that can drive the valve core to rotate or slide through an electric actuator, such as a motor or servo mechanism, to connect any two of the three passages (A / B / C). The aforementioned electric actuator can be understood as a device that converts electrical energy into mechanical motion, including a motor, gearbox, lead screw, etc., which can be used to drive the valve core of the three-way valve to switch states. The aforementioned controller can be understood as the core control unit of the compressed gas energy storage device, which connects all electric three-way valves via electrical signals, receives sensor data, and executes preset control logic. The specific selection of the electric valve is not specifically limited in this embodiment; electric three-way ball valves, electric three-way butterfly valves, or other types of electric valves can be used. The aforementioned controller may include a programmable logic controller, an input module equipped with analog quantities such as temperature and pressure signals, and a relay output module for controlling the valve motor. The aforementioned valve is designed to allow the three-way valve to handle switching between different modes.

[0078] In this embodiment, by using an electric three-way valve and an electric actuator, rapid and precise switching of the states of each passage is achieved; through the electrical connection between the controller and the electric three-way valve, an automated control system is constructed, which can dynamically adjust the valve state according to real-time data such as thermal or cold storage temperature and grid load, ensuring the reliable operation of the compressed gas energy storage device in multiple modes such as thermal storage, cold storage, and power generation, and improving the system's operating efficiency and flexibility.

[0079] In some alternative implementations, handle-driven ball valves or butterfly valves can be used, with the valve core switching the passage by rotation or sliding. Alternatively, multiple three-way valve handles can be connected in series using mechanical components such as gears or linkages to achieve synchronous switching. For example, a single master linkage can be used to connect all valve handles, allowing operation of a single handle to synchronously change the state of all valve passages, ensuring consistent fluid paths when switching between thermal storage and power generation modes.

[0080] Optionally, the heat storage device 13 and the cold storage device 14 are filled with metal particles, rock particles or phase change material microcapsules.

[0081] In this embodiment, metal particles, such as iron and aluminum, and rock particles, such as sand and basalt, are all inexpensive materials. Rock particles, in particular, can be sourced locally, reducing the cost of thermal and cold storage media. Furthermore, metal particles have high thermal conductivity, making them suitable for high-frequency charging and discharging scenarios. Although rock particles have lower thermal conductivity, the thermal storage capacity can be increased by increasing the filling amount. The physical and chemical properties of metal and rock particles are stable, allowing them to withstand the high temperatures of the thermal storage subsystem and the low temperatures of the cold storage subsystem, avoiding the risk of molten salt dissociation or solidification at high temperatures.

[0082] Phase change material (PCM) microcapsules, encapsulated in a shell, prevent liquid leakage during the phase change process. Simultaneously, dispersed filling reduces the influence of the thermocline, improving temperature stability during heat storage and release, and mitigating the "outlet temperature fluctuation" problem. The three materials mentioned above can be used individually or in combination: for example, metal particles and rock particles balance thermal conductivity and cost, making them suitable for conventional compressed air energy storage scenarios; PCM microcapsules and rock particles, while maintaining low cost, optimize temperature profiles through PCM, making them suitable for industrial waste heat recovery or LNG cold energy utilization scenarios with high temperature stability requirements.

[0083] This implementation achieves a balance between cost, efficiency, and stability, satisfying the core requirements of "reducing system costs" and "avoiding molten salt defects," while also improving energy storage performance, reducing temperature fluctuations, and enhancing system stability through innovative media such as phase change materials.

[0084] Of course, other filler materials can also be selected, such as alumina, silicon carbide particles or graphene nanoparticles; however, the embodiments of this application do not specifically limit this.

[0085] Optionally, the heat transfer medium of the thermal storage subsystem and the cold storage subsystem includes at least one of air, nitrogen, argon and helium.

[0086] In this embodiment, air has extremely low cost, is taken from the atmosphere, requires no additional preparation, and is suitable for ambient or medium-temperature thermal storage scenarios. In the charging subsystem, air can act as a heat transfer medium to absorb the compression heat generated by the compressor, which is then transferred to the thermal storage tank 13 via the high-temperature heat exchanger 3. In the cold storage subsystem, air flows through the low-temperature heat exchanger 8 to absorb the cold energy released by the expander and is stored in the cold storage tank 14. Nitrogen is chemically inert, non-flammable, and does not support combustion, making it suitable for high-temperature thermal storage or flammable and explosive environments. In the thermal storage subsystem, nitrogen can prevent reaction with metal pipes at high temperatures, improving system safety. In the cold and heat energy generation system, nitrogen can act as a working medium in the compression-expansion cycle to drive the generator. Argon has a low thermal conductivity but a high specific heat capacity, making it suitable for low-temperature cold storage scenarios. In LNG cold energy recovery scenarios, argon can efficiently absorb low-temperature cold energy, preventing water vapor condensation from affecting cold storage efficiency. Helium has a high thermal conductivity and is an ideal low-temperature heat transfer medium. In cryogenic energy storage subsystems (such as liquid hydrogen energy storage), helium can rapidly transfer cold energy while reducing flow resistance due to its low viscosity. The selection of "at least one" of the above-mentioned working fluids supports single or mixed working fluids, such as a combination of air and nitrogen, to meet energy storage needs in different temperature ranges. For example: air for ambient temperature thermal storage, nitrogen for high temperature thermal storage, and helium for cryogenic energy storage.

[0087] In addition, other gases such as carbon dioxide and neon can also be used. Different gas choices do not affect the realization of the basic functions of the embodiments of this application.

[0088] In this embodiment, by selecting gases such as air, nitrogen, argon, and helium as heat transfer media, the high cost and solidification risk of molten salt thermal energy storage are avoided by leveraging their low cost and easy availability. Utilizing the physical properties of the gaseous media, such as the universality of air, the inertness of nitrogen, and the high thermal conductivity of helium, solar thermal energy, industrial waste heat, and LNG cold energy can be efficiently recovered, improving the system's energy storage efficiency. Simultaneously, it supports flexible operation in multiple scenarios, such as industrial heating or cooling, and residential energy supply, enabling flexible absorption and release of thermal energy.

[0089] In this embodiment, the system includes a thermal storage subsystem, a cold storage subsystem, and a thermal energy generation system. The thermal storage subsystem includes a first motor 23, a first compressor 12, and a thermal storage tank 13. The outlet of the first compressor 12 is connected to the inlet of the thermal storage tank 13, and the first motor 23 is electrically connected to the first compressor 12. The cold storage subsystem includes a cold storage tank 14. The thermal energy generation system includes a second compressor 16 and a first expander 17 coaxially arranged. A first three-way valve 21 and a second three-way valve 19 are provided on the pipeline. The first passage of the first three-way valve 21 is connected to the outlet pipeline of the cold storage tank 14, the second passage is connected to the inlet pipeline of the second compressor 16, and the third passage is connected to the inlet pipeline of the cold storage tank 14. The fourth passage of the second three-way valve 19 is connected to the outlet pipeline of the thermal storage tank 13, the fifth passage is connected to the inlet pipeline of the first expander 17, and the sixth passage is connected to the outlet pipeline of the first compressor 12. The second compressor 16 is connected to the inlet pipeline of the thermal storage tank 13 via a pipeline. In this embodiment, the first compressor 12 in the thermal storage subsystem compresses the gaseous working fluid to a higher temperature, enabling the extraction and storage of heat energy generated during the compressed gas energy storage charging process in the thermal storage unit 13. This eliminates the need for expensive molten salt thermal storage, reducing costs. Simultaneously, the cold energy released by the expanding gas in the discharging system is stored in the cold storage subsystem, achieving cold energy recovery and avoiding energy waste. The second compressor 16 and the first expander 17, coaxially arranged in the thermal and cold energy discharging system, convert the stored high-grade thermal and cold energy into electrical energy, providing flexible power output. Furthermore, the first three-way valve 21 and the second three-way valve 19 on the pipeline, along with their connections, allow for fluid path switching between different modes such as thermal storage, cold storage, and power generation, ensuring continuous and stable charging and discharging of the compressed gas energy storage system and improving the stability of the compressed gas energy storage device during charging and discharging.

[0090] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the utility model involved in this application is not limited to the technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this application.

[0091] Apart from the technical features described in the specification, the other technical features are known to those skilled in the art. To highlight the innovative features of this utility model, the other technical features will not be described in detail here.

Claims

1. A compressed gas energy storage device, characterized by, The device includes: Thermal energy storage subsystem, cold energy storage subsystem, and thermal energy generation subsystem; The thermal storage subsystem includes a first motor, a first compressor, and a thermal storage device. The outlet of the first compressor is connected to the inlet of the thermal storage device, and the first motor is electrically connected to the first compressor. The cold storage subsystem includes a cold storage unit, and the cold and heat energy generation electronic system includes a second compressor and a first expander arranged coaxially, with a first three-way valve and a second three-way valve installed on the pipeline; The first passage of the first three-way valve is connected to the outlet pipe of the cold storage tank, the second passage is connected to the inlet pipe of the second compressor, and the third passage is connected to the inlet pipe of the cold storage tank. The fourth passage of the second three-way valve is connected to the outlet pipe of the heat storage tank, the fifth passage is connected to the inlet pipe of the first expander, the sixth passage is connected to the outlet pipe of the first compressor, and the second compressor is connected to the inlet pipe of the heat storage tank through a pipe.

2. The apparatus of claim 1, wherein, The device further includes a gas storage system, a charging subsystem, and a discharge system. The charging subsystem includes a third compressor and a high-temperature heat exchanger connected to each other. The high-temperature heat exchanger includes a seventh passage and an eighth passage. The gas outlet of the seventh passage is connected to the first compressor through a pipe. The gas storage system is connected to the gas outlet of the eighth passage. The discharge system includes a second expander and a cryogenic heat exchanger connected to each other. The cryogenic heat exchanger has a ninth passage and a tenth passage. The outlet of the ninth passage is connected to the outside, and the outlet of the tenth passage is connected to the cold storage unit. The outlet of the gas storage system is connected to the inlet of the second expander through a pipe.

3. The apparatus of claim 2, wherein, The electron discharge system includes at least one second expander connected in series.

4. The apparatus of claim 2, wherein, The charging subsystem includes at least one third compressor connected in series.

5. The device of any one of claims 2 to 4, wherein, The outlet of the heat storage device forms a circulation pipeline with the seventh passage inlet of the high-temperature heat exchanger through the second three-way valve and the third three-way valve; The sixth passage inlet of the second three-way valve is connected to the outlet of the first compressor via a pipe, the inlet of the first compressor is connected to the seventh passage via a pipe, and the fourth passage of the second three-way valve is connected to the inlet of the heat storage tank via a pipe. The outlet of the heat storage tank is connected to the eleventh passage of the third three-way valve via a pipe, the twelfth passage of the third three-way valve is connected to the inlet of the seventh passage via a pipe, and the second compressor is connected to the heat storage tank via the thirteenth passage of the third three-way valve.

6. The device of any one of claims 2 to 4, wherein, The cold storage subsystem includes a cold storage unit and a circulating fan; The outlet of the cold storage unit forms a circulation pipe with the tenth passage inlet of the low-temperature heat exchanger through the first three-way valve and the fourth three-way valve; The tenth passage inlet is connected to the outlet of the circulating fan via a pipe, the inlet of the circulating fan is connected to the fourteenth passage of the fourth three-way valve via a pipe, the fifteenth passage of the fourth three-way valve is connected to the outlet of the cold storage unit via a pipe, and the sixteenth passage of the fourth three-way valve is connected to the first expander via a pipe. The inlet of the cold storage unit is connected to the first passage of the first three-way valve via a pipe, and the third passage of the first three-way valve is connected to the tenth passage outlet of the low-temperature heat exchanger via a pipe.

7. The device of any one of claims 2 to 4, wherein, The high-temperature heat exchanger and the low-temperature heat exchanger are dual-pass counter-flow pipe structures, with the seventh passage and the eighth passage having opposite flow directions, and the ninth passage and the tenth passage having opposite flow directions.

8. The device of any one of claims 2 to 4, wherein, The first three-way valve, the second three-way valve, the third three-way valve, and the fourth three-way valve are electric three-way valves, which switch the passage state through an electric actuator; the compressed gas energy storage device also includes a controller, which is electrically connected to the first three-way valve, the second three-way valve, the third three-way valve, and the fourth three-way valve.

9. The device of any one of claims 1 to 4, wherein, The heat storage and cold storage devices are filled with metal particles, rock particles, or phase change material microcapsules in their packed beds.

10. The device of any one of claims 1 to 4, wherein, The heat transfer medium of the thermal storage subsystem and the cold storage subsystem includes at least one of air, nitrogen, argon and helium.

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