Deep underground damless pumped compressed air energy storage pressure vessel and operation method

Abstract

A deep underground damless pumped compressed air energy storage pressure vessel and its operating method include a water reservoir, an air and water mixing reservoir, and an air reservoir arranged in sequence from top to bottom. The water reservoir, the air and water mixing reservoir, and the air reservoir are interconnected by a central vertical shaft. The central vertical shaft contains a first pressure pipe, a second pressure pipe, a third pressure pipe, and a fourth pressure pipe, respectively. The first pressure pipe connects the integrated pumped storage turbine and the air and water mixing reservoir; the second pressure pipe connects the air compressor and the air and water mixing reservoir; the third pressure pipe connects the air turbine generator set and the air reservoir; and the fourth pressure pipe connects the air compressor and the air reservoir. The present invention reduces construction costs, saves land, reduces excavation, support, and lining costs of the pressure vessel system, shortens construction period, and improves the stability of the pressure vessel during operation through reasonable cross-sectional design and vertical and horizontal layout planning.

Description

Technical Field

[0001] The present invention relates to an energy storage pressure vessel, and in particular to a deep underground damless water pumping compressed air energy storage pressure vessel. Background Art

[0002] As China builds a clean, low-carbon energy system, the large-scale integration of intermittent renewable energy sources like wind and solar power poses challenges to the safe and efficient operation of power systems. Energy storage is a key approach to addressing this challenge. Damless pumped compressed air energy storage offers advantages over chemical energy storage, flywheel energy storage, and traditional pumped hydro storage, such as high efficiency, low investment, long lifespan, and environmental friendliness, making it suitable for large-scale deployment.

[0003] There is no technical content to refer to in the existing technology. Summary of the Invention

[0004] The technical problem to be solved by the present invention is: how to construct a pressure vessel system for a damless pumped compressed air energy storage power station built deep underground to meet the needs of high-power energy storage power stations for high-pressure, large-capacity, and high-performance pressure vessels.

[0005] The technical solution of the present invention is specifically as follows:

[0006] A deep underground damless pumped compressed air energy storage pressure vessel comprises a water reservoir, an air and water mixing reservoir and an air reservoir arranged in sequence from top to bottom. The water reservoir, the air and water mixing reservoir and the air reservoir are interconnected by a central vertical shaft. A first pressure pipe, a second pressure pipe, a third pressure pipe and a fourth pressure pipe are respectively arranged in the central vertical shaft. The first pressure pipe is connected to the air compressor air and water mixing reservoir; the second pressure pipe is connected to the water inlet end of the pumped storage integrated turbine and the air and water mixing reservoir; the third pressure pipe is connected to the air turbine generator set and the air and water mixing reservoir; the fourth pressure pipe is connected to the air turbine generator set and the air reservoir; and the fifth pressure pipe is connected to the air compressor and the air reservoir.

[0007] The reservoir includes at least three horizontally arranged transverse reservoir tunnels and one vertically arranged longitudinal reservoir tunnel. The longitudinal reservoir tunnel is arranged vertically at the end of the transverse reservoir tunnel and connects several transverse reservoir tunnels. The longitudinal reservoir tunnel is connected to the water inlet pipe and the tailwater pipe, wherein the tailwater pipe is connected to the tailwater outlet of the pumped-storage integrated turbine, and the water inlet pipe is connected to the water inlet of the pumped-storage integrated turbine.

[0008] The capacity of the reservoir is 130×10 4 m 3, the pressure is atmospheric pressure; the bottom elevation of the horizontal reservoir tunnel is -40.0m, the top elevation is -20.0m, the cross-section is a circular arch, 30m wide and 20m high, of which the vertical section length is 13.2m, the arc radius is 20m, the length of the horizontal reservoir tunnel is 400m, and the spacing is 60m; the bottom elevation of the longitudinal reservoir tunnel is -40.0m, the top elevation is -20.0m, the cross-section is a circular arch, 30m wide and 20m high, of which the vertical section length is 13.2m, the arc radius is 20m, and the length of the longitudinal reservoir tunnel is 270m.

[0009] The air and water mixing reservoir includes three groups of vertical tunnels arranged in parallel. The first longitudinal mixing tunnel and the second longitudinal mixing tunnel are set at the ends of the vertical tunnel groups. The first longitudinal mixing tunnel and the second longitudinal mixing tunnel are interconnected with each group of vertical tunnel groups. Then, the first longitudinal mixing tunnel is connected to the first pressure pipe and the second pressure pipe, and the second longitudinal mixing tunnel is connected to the third pressure pipe.

[0010] Each group of vertical tunnels includes several vertical tunnels arranged vertically in parallel. The upper ends of all vertical tunnels are connected to the first transverse mixed tunnel, and the lower ends are connected to the second transverse mixed tunnel; moreover, the first transverse mixed tunnel is connected to the first longitudinal mixed tunnel, and the second transverse mixed tunnel is connected to the second longitudinal mixed tunnel.

[0011] The capacity of the air and water mixing reservoir is 125×10 4 m 3 , pressure is 7.5MPa; the vertical tunnel bottom elevation is -151m, the top elevation is -89m, the cross section is circular, the circular cross section diameter is 8m, the tunnel length is 62m, and the spacing is 20m; the first horizontal mixed tunnel bottom elevation is -89.0m, the top elevation is -80.0m, the cross section is arc-shaped, 16m wide, 9m high, of which the vertical section length is 10.6m, the arc radius is 16m, and the length of the first horizontal mixed tunnel is 260m; the second horizontal mixed tunnel bottom elevation is -160.0m, the top elevation is -151.0m, the cross section is arc-shaped, 16m wide, 9m high, of which the vertical section length is 10 .6m, the arc radius is 16m, and the length of the second horizontal mixed tunnel is 260m; the bottom elevation of the first longitudinal mixed tunnel is -100.0m, the top elevation is -80.0m, the cross-section is an arc arch, 30m wide and 20m high, of which the vertical section length is 13.2m, the arc radius is 20m, and the length of the first longitudinal mixed tunnel is 216m; the bottom elevation of the second longitudinal mixed tunnel is -160.0m, the top elevation is -140.0m, the cross-section is an arc arch, 30m wide and 20m high, of which the vertical section length is 13.2m, the arc radius is 20m, and the length of the second longitudinal mixed tunnel is 216m.

[0012] The air reservoir includes a plurality of mutually parallel transverse air tunnels and a plurality of mutually parallel longitudinal air tunnels, and the transverse air tunnels and the longitudinal air tunnels are arranged vertically; wherein the longitudinal air tunnels are connected to the fourth pressure pipe and the fifth pressure pipe.

[0013] There are ten transverse air tunnels, with a spacing of 100m between adjacent transverse air tunnels; there are four longitudinal air tunnels, with a spacing of 227m between adjacent longitudinal air tunnels. The four longitudinal air tunnels are located in the middle and at both ends of the transverse air tunnels respectively; the capacity of the air reservoir is 210×10 4 m 3 , pressure is 10MPa; the bottom elevation of the horizontal air tunnel is -209m, the top elevation is -200m, the cross-section is an arc arch, 30m wide and 9m high, the vertical section length is 5.0m, the arc radius is 30m, and the length of the horizontal air tunnel is 800m; the bottom elevation of the longitudinal air tunnel is -209m, the top elevation is -200m, the cross-section is an arc arch, 30m wide and 9m high, the vertical section length is 5.0m, the arc radius is 30m, and the length of the longitudinal air tunnel is 800m.

[0014] The cross section of the central shaft is circular, with a diameter of 10m, a height of 189m, a top elevation of -20.0m, and a bottom elevation of -209.0m. It is arranged in the center of the ends of the three types of reservoirs.

[0015] Operation method of energy storage pressure vessel,

[0016] (a) In the initial stage, the air compressor compresses the air and injects the compressed air into the air-water mixing reservoir and the air reservoir through the first pressure pipe and the fifth pressure pipe of the central shaft, respectively, so that the air-water mixing reservoir reaches the design pressure of 7.5 MPa and the air reservoir (3) reaches the design pressure of 10 MPa;

[0017] (b) Power generation: High-pressure air in the air reservoir is released through the fourth pressure pipe to the air turbine generator set to generate electricity. Subsequently, the air enters the air-water mixing reservoir of the third pressure pipe at a back pressure of 7.5 MPa, and the water in the air-water mixing reservoir is pushed into the pumped-storage integrated turbine to generate electricity. The tailwater after power generation enters the reservoir through the tailwater pipe. When the water level in the reservoir reaches a predetermined height, power generation terminates.

[0018] (c) Energy storage: The pumped-storage integrated turbine pumps water from the water inlet forebay through the second pressure pipe to the air-water mixing reservoir. At the same time, the 7.5MPa air in the air-water mixing reservoir is sent to the air compressor through the first pressure pipe and compressed to 10MPa. The compressor then sends the air to the air reservoir through the fifth pressure pipe. When the overall pressure of the air reservoir reaches 10MPa, the energy storage stage ends.

[0019] The beneficial effects of the present invention are as follows: the present invention constructs a pressure vessel system suitable for a deep underground damless pumped compressed air energy storage power station, the design capacity of which is 300MW. The pressure vessel system consists of three types of reservoirs, namely (1) a water reservoir with a design capacity of 130×10 4 m 3 , the design pressure is atmospheric pressure; (2) air and water mixing reservoir, the design capacity is 125×10 4 m 3 , the design pressure is 7.5MPa; (3) air storage, the design capacity is 210×10 4 m 3 , with a design pressure of 10MPa. Different cross-sectional forms and layout methods were designed for the three types of reservoirs in the pressure vessel system, and the three reservoirs were connected by a central vertical shaft. Through reasonable cross-sectional design and vertical and horizontal layout planning, this pressure vessel system reduces project costs, saves land, reduces the costs of excavation, support, and lining of the pressure vessel system, shortens the construction period, and improves the stability of the pressure vessel during operation, providing technical support and guarantee for the safe and efficient operation of damless pumped compressed air energy storage power stations. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Schematic diagram of the overall structure of the pressure vessel of the present invention;

[0021] Figure 2 This is a schematic diagram of the reservoir structure;

[0022] Figure 3 It is a structural diagram of the air and water mixing reservoir;

[0023] Figure 4 This is a structural diagram of the air storage. DETAILED DESCRIPTION

[0024] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0025] In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as limiting the present invention.

[0026] like Figure 1 As shown, a deep underground damless pumped compressed air energy storage pressure vessel includes a water reservoir 1, an air and water mixing reservoir 2 and an air reservoir 3 arranged in sequence from top to bottom. The water reservoir 1, the air and water mixing reservoir 2 and the air reservoir 3 are interconnected by a central vertical shaft 4. The central vertical shaft 4 is arranged in the center of the ends of the three reservoirs. There are several pressure pipes in the central vertical shaft, among which the first pressure pipe is connected to the air compressor air and water mixing reservoir 2; the second pressure pipe is connected to the water inlet end of the pumped storage integrated turbine and the air and water mixing reservoir 2; the third pressure pipe is connected to the air turbine generator set and the air and water mixing reservoir 2; the fourth pressure pipe is connected to the air turbine generator set and the air reservoir 3; and the fifth pressure pipe is connected to the air compressor and the air reservoir 3.

[0027] like Figure 2 As shown, reservoir 1 includes at least three horizontally arranged transverse reservoir tunnels 5 and one vertically arranged longitudinal reservoir tunnel 6. The longitudinal reservoir tunnel 6 is arranged perpendicular to the ends of the transverse reservoir tunnels 5 and connects several transverse reservoir tunnels 5. The longitudinal reservoir tunnel 6 is connected to the inlet pipe and the tailrace pipe, which are located in the surrounding medium. The tailrace pipe is connected to the tailrace outlet of the pumped-storage integrated turbine, and the inlet pipe is connected to the water inlet of the pumped-storage integrated turbine.

[0028] Furthermore, the optimal implementation is that the number of the transverse reservoir tunnels 5 is five.

[0029] Furthermore, the design capacity of reservoir 1 is 130×10 4 m 3 , the design pressure is atmospheric pressure. The horizontal reservoir tunnel 5 has a bottom elevation of -40.0m and a top elevation of -20.0m. It has a circular arch cross-section, is 30m wide and 20m high, with a vertical section length of 13.2m and a circular radius of 20m. The horizontal reservoir tunnel 5 is 400m long and has a spacing of 60m. The vertical reservoir tunnel 6 has a bottom elevation of -40.0m and a top elevation of -20.0m. It has a circular arch cross-section, is 30m wide and 20m high, with a vertical section length of 13.2m and a circular radius of 20m. The longitudinal reservoir tunnel 6 is 270m long.

[0030] like Figure 3As shown, the air-water mixing reservoir 2 includes three groups of parallel vertical tunnels 7. A first longitudinal mixing tunnel 11 and a second longitudinal mixing tunnel 12 are provided at the ends of the vertical tunnel groups 7. The first longitudinal mixing tunnel 11 and the second longitudinal mixing tunnel 12 are interconnected with each group of vertical tunnels 7. Then, the first longitudinal mixing tunnel 11 is connected to the first pressure pipe and the second pressure pipe respectively, and the second longitudinal mixing tunnel 12 is connected to the third pressure pipe. The first pressure pipe is connected to the air compressor, the second pressure pipe is connected to the water inlet of the pumped storage integrated turbine, and the third pressure pipe is connected to the air turbine generator set. It should be noted that the first pressure pipe, the second pressure pipe, and the third pressure pipe are all located in the central shaft 4.

[0031] Among them, each group of vertical tunnels 7 includes several vertical tunnels 8 arranged vertically in parallel, the upper ends of all vertical tunnels 8 are connected to the first horizontal mixing tunnel 9, and the lower ends are connected to the second horizontal mixing tunnel 10; moreover, the first horizontal mixing tunnel 9 is connected to the first longitudinal mixing tunnel 11, and the second horizontal mixing tunnel 10 is connected to the second longitudinal mixing tunnel 12.

[0032] Furthermore, the distance between adjacent vertical tunnel groups 7 is 84 m. In each vertical tunnel group 7, the number of vertical tunnels 8 is determined according to the situation, and can be ten as shown in the figure, or more.

[0033] Furthermore, the design capacity of the air and water mixing reservoir 2 is 125×10 4 m 3 , with a design pressure of 7.5MPa. Vertical tunnel 8 has a bottom elevation of -151m and a top elevation of -89m. It has a circular cross-section with an 8m diameter, a tunnel length of 62m, and a spacing of 20m. The first horizontal mixed tunnel 9 has a bottom elevation of -89.0m and a top elevation of -80.0m. It has an arc-shaped cross-section with a width of 16m and a height of 9m. The vertical section of the cross-section is 10.6m long, with a radius of 16m. The first horizontal mixed tunnel 9 is 260m long. The second horizontal mixed tunnel 10 has a bottom elevation of -160.0m and a top elevation of -151.0m. It has an arc-shaped cross-section with a width of 16m and a height of 9m. The vertical section of the cross-section is 10.6m long, with a radius of 16m. The second horizontal mixed tunnel 10 is 260m long. The first longitudinal mixed tunnel 11 has a bottom elevation of -100.0m and a top elevation of -80.0m. It has an arc-shaped cross-section, is 30m wide and 20m high, with a vertical section length of 13.2m and a circular arc radius of 20m. The first longitudinal mixed tunnel 11 is 216m long. The second longitudinal mixed tunnel 12 has a bottom elevation of -160.0m and a top elevation of -140.0m. It has an arc-shaped cross-section, is 30m wide and 20m high, with a vertical section length of 13.2m and a circular arc radius of 20m. The second longitudinal mixed tunnel 12 is 216m long.

[0034] like Figure 4 As shown, the air storage 3 includes several mutually parallel transverse air tunnels 13 and several mutually parallel longitudinal air tunnels 14, and the transverse air tunnels 13 and the longitudinal air tunnels 14 are arranged vertically; wherein, the longitudinal air tunnel 14 is connected to the fourth pressure pipe and the fifth pressure pipe, wherein the fourth pressure pipe is connected to the air turbine generator set, and the fifth pressure pipe is connected to the air compressor, and the fourth pressure pipe and the fifth pressure pipe are both located in the central shaft 4.

[0035] Furthermore, there are ten transverse air tunnels 13, with a spacing of 100 meters between adjacent transverse air tunnels 13; there are four longitudinal air tunnels 14, with a spacing of 227 meters between adjacent longitudinal air tunnels 14. The four longitudinal air tunnels 14 are located in the middle and at both ends of the transverse air tunnels 13. It should be noted that when four longitudinal air tunnels 14 are provided, the endmost longitudinal air tunnel 14 is connected to the central shaft 4, and all transverse air tunnels 13 are connected to each longitudinal air tunnel 14.

[0036] Furthermore, the design capacity of the air bank 3 is 210×10 4 m 3 , the design pressure is 10MPa.

[0037] Transverse air tunnel 13 has a bottom elevation of -209m and a top elevation of -200m. It has an arc-shaped cross-section, is 30m wide and 9m high, with a vertical section of 5.0m long and a circular radius of 30m. Transverse air tunnel 13 is 800m long. Longitudinal air tunnel 14 has a bottom elevation of -209m and a top elevation of -200m. It has an arc-shaped cross-section, is 30m wide and 9m high, with a vertical section of 5.0m long and a circular radius of 30m. Longitudinal air tunnel 14 is 800m long.

[0038] The cross section of the central shaft 4 is circular, with a diameter of 10m, a height of 189m, a top elevation of -20.0m, and a bottom elevation of -209.0m. It is arranged in the center of the ends of the three types of reservoirs.

[0039] Reservoir 1, air-water mixing reservoir 2, and air reservoir 3 can all be excavated and lined in a mountainous area with suitable surrounding rock, regional structure, geostress, and groundwater conditions. Excavation can be carried out using mining methods or shield tunneling. The lining is constructed with steel plates, with a thickness generally ranging from 8 to 12 mm, determined based on the surrounding rock, geostress, and other conditions.

[0040] The operating mode of the present invention is:

[0041] (a) In the initial stage, the air compressor compresses the air and injects the compressed air into the air-water mixing tank 2 and the air tank 3 through the first pressure pipe and the fifth pressure pipe of the central shaft 4, respectively, so that the air-water mixing tank 2 reaches the design pressure of 7.5 MPa and the air tank 3 reaches the design pressure of 10 MPa.

[0042] (b) Power generation: The high-pressure air in the air reservoir 3 is released into the air turbine generator set through the fourth pressure pipe to generate electricity. Subsequently, the air enters the air and water mixing reservoir 2 through the third pressure pipe at a back pressure of 7.5 MPa, and the water in the air and water mixing reservoir 2 is pushed into the pumped-storage integrated turbine to generate electricity. The tailwater after power generation enters the reservoir 1 through the tailwater pipe. When the water in the reservoir 1 reaches a predetermined height, power generation terminates.

[0043] (c) Energy storage: The pumped-storage integrated turbine pumps water from the water inlet forebay through the second pressure pipe to the air-water mixing reservoir 2. At the same time, the 7.5 MPa air in the air-water mixing reservoir 2 is sent to the air compressor through the first pressure pipe and compressed to 10 MPa. The compressor then sends the air to the air reservoir 3 through the fifth pressure pipe. When the overall pressure of the air reservoir 3 reaches 10 MPa, the energy storage stage ends.

[0044] The present invention fully utilizes the stress of underground surrounding rock, has a compact layout, can fully utilize underground space, and has the characteristics of large scale, high efficiency, and stable operation. It is the key to promoting the application of damless pumping compressed air energy storage technology.

[0045] The above is only a preferred embodiment of the present invention. It should be pointed out that for those skilled in the art, several changes and improvements can be made without departing from the overall concept of the present invention, and these should also be regarded as the scope of protection of the present invention.

Claims

1. A deep underground damless pumped compressed air energy storage pressure vessel, characterized by: The invention comprises a water reservoir (1), an air and water mixing reservoir (2) and an air reservoir (3) which are arranged in sequence from top to bottom. The water reservoir (1), the air and water mixing reservoir (2) and the air reservoir (3) are interconnected by a central shaft (4). A first pressure pipe, a second pressure pipe, a third pressure pipe and a fourth pressure pipe are respectively arranged in the central shaft (4). The first pressure pipe is connected to the air compressor air and water mixing reservoir (2); the second pressure pipe is connected to the water inlet end of the pumped storage integrated turbine and the air and water mixing reservoir (2); the third pressure pipe is connected to the air turbine generator set and the air and water mixing reservoir (2); the fourth pressure pipe is connected to the air turbine generator set and the air reservoir (3); and the fifth pressure pipe is connected to the air compressor and the air reservoir (3). The reservoir (1) includes at least three horizontally arranged transverse reservoir tunnels (5) and one vertically arranged longitudinal reservoir tunnel (6), wherein the longitudinal reservoir tunnel (6) is arranged vertically at the end of the transverse reservoir tunnel (5) and connects a plurality of transverse reservoir tunnels (5); the longitudinal reservoir tunnel (6) is connected to an inlet pipe and a tailwater pipe, wherein the tailwater pipe is connected to the tailwater outlet of the pumped-storage integrated turbine, and the inlet pipe is connected to the water inlet of the pumped-storage integrated turbine; The air and water mixing reservoir (2) includes three groups of vertical tunnels (7) arranged in parallel. A first longitudinal mixing tunnel (11) and a second longitudinal mixing tunnel (12) are provided at the ends of the vertical tunnel groups (7). The first longitudinal mixing tunnel (11) and the second longitudinal mixing tunnel (12) are both connected to each group of vertical tunnel groups (7). Then, the first longitudinal mixing tunnel (11) is connected to the first pressure pipe and the second pressure pipe, and the second longitudinal mixing tunnel (12) is connected to the third pressure pipe. The air reservoir (3) includes a plurality of mutually parallel transverse air tunnels (13) and a plurality of mutually parallel longitudinal air tunnels (14), wherein the transverse air tunnels (13) and the longitudinal air tunnels (14) are arranged vertically; wherein the longitudinal air tunnels (14) are connected to the fourth pressure pipe and the fifth pressure pipe.

2. The deep underground damless pumped compressed air energy storage pressure vessel according to claim 1, characterized in that: The capacity of the reservoir (1) is 130×10 4 m 3 , the pressure is atmospheric pressure; the bottom elevation of the horizontal reservoir tunnel (5) is -40.0m, the top elevation is -20.0m, the cross section is a circular arch, 30m wide and 20m high, the vertical section length of the cross section is 13.2m, the arc radius is 20m, the length of the horizontal reservoir tunnel (5) is 400m, and the spacing is 60m; the bottom elevation of the longitudinal reservoir tunnel (6) is -40.0m, the top elevation is -20.0m, the cross section is a circular arch, 30m wide and 20m high, the vertical section length of the cross section is 13.2m, the arc radius is 20m, and the length of the longitudinal reservoir tunnel (6) is 270m.

3. The deep underground damless pumped compressed air energy storage pressure vessel according to claim 1 is characterized in that: Each vertical tunnel group (7) includes a plurality of vertical tunnels (8) arranged vertically and in parallel. The upper ends of all vertical tunnels (8) are connected to the first transverse mixing tunnel (9), and the lower ends thereof are connected to the second transverse mixing tunnel (10). Furthermore, the first transverse mixing tunnel (9) is connected to the first longitudinal mixing tunnel (11), and the second transverse mixing tunnel (10) is connected to the second longitudinal mixing tunnel (12).

4. The deep underground damless pumped compressed air energy storage pressure vessel according to claim 3 is characterized in that: The capacity of the air and water mixing reservoir (2) is 125×10 4 m 3 , the pressure is 7.5MPa; the vertical tunnel (8) has a bottom elevation of -151m, a top elevation of -89m, a circular cross section with a diameter of 8m, a tunnel length of 62m, and a spacing of 20m; The first horizontal mixed tunnel (9) has a bottom elevation of -89.0m and a top elevation of -80.0m. Its cross section is an arc arch, with a width of 16m and a height of 9m. The vertical section of the cross section is 10.6m long and the arc radius is 16m. The length of the first horizontal mixed tunnel (9) is 260m. The second horizontal mixed tunnel (10) has a bottom elevation of -160.0m and a top elevation of -151.0m. Its cross section is an arc arch, with a width of 16m and a height of 9m. The vertical section of the cross section is 10.6m long and the arc radius is 16m. The length of the second horizontal mixed tunnel (10) is 260m. The first longitudinal mixed tunnel (11) has a bottom elevation of -100.0m and a top elevation of -80.0m. Its cross section is an arc arch, with a width of 30m and a height of 20m. The vertical section of the cross section is 13.2m long and the arc radius is 20m. The length of the first longitudinal mixed tunnel (11) is 216m. The second longitudinal mixed tunnel (12) has a bottom elevation of -160.0m and a top elevation of -140.0m. Its cross section is an arc arch with a width of 30m and a height of 20m. The vertical section of the cross section is 13.2m long and the arc radius is 20m. The length of the second longitudinal mixed tunnel (12) is 216m.

5. The deep underground damless pumped compressed air energy storage pressure vessel according to claim 1, characterized in that: There are ten transverse air tunnels (13), with a spacing of 100 m between adjacent transverse air tunnels (13); there are four longitudinal air tunnels (14), with a spacing of 227 m between adjacent longitudinal air tunnels (14), and the four longitudinal air tunnels (14) are located in the middle and at both ends of the transverse air tunnel (13); the capacity of the air reservoir (3) is 210×10 4 m 3 , the pressure is 10MPa; the bottom elevation of the horizontal air tunnel (13) is -209m, the top elevation is -200m, the cross section is a circular arch, 30m wide and 9m high, the vertical section length is 5.0m, the arc radius is 30m, and the length of the horizontal air tunnel (13) is 800m; the bottom elevation of the longitudinal air tunnel (14) is -209m, the top elevation is -200m, the cross section is a circular arch, 30m wide and 9m high, the vertical section length is 5.0m, the arc radius is 30m, and the length of the longitudinal air tunnel (14) is 800m.

6. The deep underground damless pumped compressed air energy storage pressure vessel according to claim 1, characterized in that: The central shaft (4) has a circular cross-section, a diameter of 10m, a height of 189m, a top elevation of -20.0m, and a bottom elevation of -209.0m. It is located in the center of the ends of the three types of reservoirs.

7. A method for operating a deep underground damless pumped compressed air energy storage pressure vessel according to any one of claims 1 to 6, characterized in that: (a) In the initial stage, the air compressor compresses the air and injects the compressed air into the air and water mixing reservoir (2) and the air reservoir (3) through the first pressure pipe and the fifth pressure pipe of the central shaft (4), respectively, so that the air and water mixing reservoir (2) reaches the design pressure of 7.5 MPa and the air reservoir (3) reaches the design pressure of 10 MPa; (b) Power generation: The high-pressure air in the air reservoir (3) is released to the air turbine generator set through the fourth pressure pipe to generate electricity. Subsequently, the high-pressure air enters the air and water mixing reservoir (2) through the third pressure pipe at a back pressure of 7.5 MPa, and the water in the air and water mixing reservoir (2) is pushed into the pumped storage integrated turbine to generate electricity. The tail water after power generation enters the reservoir (1) through the tail water pipe. When the water in the reservoir (1) reaches a predetermined height, power generation is terminated. (c) Energy storage: The pumped storage integrated turbine pumps the water in the water inlet forebay through the second pressure pipe to the air and water mixing reservoir (2). At the same time, the 7.5MPa air in the air and water mixing reservoir (2) is sent to the air compressor through the first pressure pipe and compressed to 10MPa. The compressor then sends the air to the air reservoir (3) through the fifth pressure pipe. When the overall pressure of the air reservoir (3) reaches 10MPa, the energy storage stage ends.

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