Pumped hydro and pump-turbine compression air energy storage system and method

Abstract

The application discloses a pumped storage and air energy storage system and method, which comprises an upper reservoir and a lower reservoir, and a upper water conduit and a lower water conduit are communicated between the upper reservoir and the lower reservoir; the upper water conduit is sequentially communicated with a first water turbine set, a water-air co-container and a second water pump and water turbine set in the direction from the upper reservoir to the lower reservoir; a first control valve is arranged between the first water turbine set and the water-air co-container, and a second control valve is arranged between the water-air co-container and the second water pump and water turbine set; and a system recovery assembly is arranged on the lower water conduit. Compared with the traditional physical energy storage technology, the application has the advantages of high efficiency, high energy density and short construction period, and can reuse the existing pumped storage power station infrastructure without adding new reservoirs and air storage facilities, so that the installed capacity of the power station is improved, the power grid regulation flexibility is significantly enhanced, and the safe and stable operation of the power system is ensured.

Description

Technical Field

[0001] This invention relates to the field of energy storage technology, and in particular to a pumped compressed air energy storage system and method relying on pumped storage and pumps and turbines. Background Technology

[0002] With the rapid development of new energy sources, new power systems urgently need novel physical energy storage technologies characterized by high energy density, high efficiency, and short construction cycles. Pumped hydro storage is currently the most mature physical energy storage technology, but it suffers from a long construction cycle. Compressed air storage has the advantages of geographical adaptability and a short construction cycle, but it suffers from low energy efficiency. In the exploration of new energy storage technologies, water-based energy storage using pumps / turbines has shown significant advantages: the energy transfer efficiency of water is as high as 90% or more, and bidirectional high-efficiency energy conversion can be achieved through mature reversible units.

[0003] Therefore, this patent proposes a pumped compressed air energy storage system and method based on pumped storage and a water pump and turbine. Summary of the Invention

[0004] The present invention aims to at least partially solve one of the technical problems in the related art.

[0005] To achieve the above objectives, this invention proposes a pumped compressed air energy storage system based on pumped storage and a pump and turbine, comprising an upper reservoir and a lower reservoir, wherein an upper water intake pipe and a lower water intake pipe are connected between the upper reservoir and the lower reservoir.

[0006] The upper water intake pipeline is sequentially connected to a first turbine unit, a water-air co-containment chamber, and a second water pump and turbine unit along the direction from the upper reservoir to the lower reservoir; a first control valve is provided between the first turbine unit and the water-air co-containment chamber, and a second control valve is provided between the water-air co-containment chamber and the second water pump and turbine unit; The lower water inlet pipe is equipped with a system recovery component.

[0007] Compared with traditional physical energy storage technologies, this invention can simultaneously combine the advantages of high efficiency, high energy density and short construction cycle. At the same time, it can deeply reuse existing pumped storage power station infrastructure without adding new reservoirs and gas storage facilities. While increasing the installed capacity of the power station, it can significantly enhance the grid regulation flexibility and ensure the safe and stable operation of the power system.

[0008] Optionally, the system recovery component includes a first water pump unit installed on the lower water intake pipe, and a third control valve is installed on the lower water intake pipe between the first water pump unit and the lower reservoir.

[0009] Furthermore, the height difference between the upper reservoir and the water-air co-containment chamber H satisfyH ≥300m.

[0010] Furthermore, the upper layer of the water-gas co-containment chamber is high-pressure gas, and the lower layer is water.

[0011] The present invention also provides a method for pumped compressed air energy storage using a system as described in any one of the above claims, comprising: During the energy storage phase, the initial gas pressure in the water-gas co-containment chamber is the first gas pressure state. The first control valve is opened to allow water from the upper reservoir to enter the water-gas co-containment chamber. During this process, the water flow drives the first turbine unit to generate electricity. When water from the upper reservoir enters the water-air co-containment chamber until the air pressure inside the chamber rises to the second air pressure state, the first control valve is closed and the second control valve is opened. The second water pump and the water pump unit in the turbine unit work to pump water from the lower reservoir into the water-air co-containment chamber until the air pressure in the water-air co-containment chamber rises to the third air pressure state, and then the second control valve is closed. During the energy release phase, the second control valve is opened, and the second water pump and the turbine unit in the turbine generator set operate. The water in the water-air co-containment chamber enters the lower reservoir after passing through the turbine unit in the second water pump turbine generator set. The water level in the chamber gradually drops to the dead water level, and then the second control valve is closed. At this time, the air pressure in the water-air co-containment chamber drops to the first air pressure state. The dead water level refers to the lowest safe position set by the water level in the water-air co-containment chamber during the energy release phase based on the requirements of maintaining the minimum operating head of the turbine and preventing gas from entering the flow channel. During the recovery phase, the water in the lower reservoir is pumped to the upper reservoir through the system recovery component to restore the initial water level of the upper reservoir during the energy storage phase.

[0012] Furthermore, both the energy storage stage and the energy release stage are isothermal processes.

[0013] Furthermore, the system efficiency when using this method... The calculation method is as follows: ; in, This represents the energy storage capacity of the energy storage system. This represents the power consumption of the energy storage system. System energy density Calculate using the following formula: ; in, The volume of the water-air co-containment chamber.

[0014] Furthermore, the energy storage capacity of the energy storage system Calculate as follows: ; in, This represents the power generation of the first turbine unit. The power generation of the second water pump and the turbine unit in the water turbine unit; Power generation of the first hydro-turbine unit The numerical calculation is as follows: ; in, The operating efficiency of the first turbine unit; V The total volume of water flowing through the first turbine unit during the process of the gas in the water-gas co-containment chamber rising from the first atmospheric pressure state to the second atmospheric pressure state; The density of the water body; h ( t The head of the first turbine unit is 1. p up The pressure of the water body inside the upper reservoir; p down ( t The pressure inside the water-air co-containment chamber is ). p 1 represents the pressure corresponding to the first pressure state of the gas in the water-gas co-containment chamber; V 1 represents the gas volume in the water-gas co-containment chamber when the gas is at the first atmospheric pressure. V ( t The total volume of water flowing into the water-air co-containment chamber after passing through the first turbine unit; The power generation of the second water pump and turbine unit when the turbine unit is operating Calculate using the following formula: ; in, The operating efficiency of the turbine unit in the second water pump turbine unit; p 2 represents the pressure corresponding to the third pressure state of the gas in the water-gas co-containment chamber.

[0015] Furthermore, the power consumption of the energy storage system Calculate as follows: ; in, The power consumption of the first water pump unit. This refers to the power consumption of the pump unit in the second water pump and turbine unit; The first water pump unit consumes power Calculate as follows: ; in, The operating efficiency of the first water pump unit; H The height difference between the upper reservoir and the water-air co-containment chamber; The power consumption of the second water pump and turbine unit during pump unit operation Calculate using the following formula: ; in, The operating efficiency of the second water pump unit; V The volume of gas inside the water-air co-containment chamber; p 3 represents the pressure corresponding to the second pressure state of the gas inside the water-gas co-containment chamber.

[0016] Further, the first air pressure < the second air pressure < the third air pressure; wherein: The pressure range of the first pressure state is 2-3 MPa; The pressure range of the second pressure state is 3-8 MPa; The pressure range of the third pressure state is 10-16 MPa.

[0017] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0018] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein: Figure 1 This is a schematic diagram of the overall structure of a pumped compressed air energy storage system based on pumped storage and a water pump and turbine according to the present invention, wherein Ⅰ is the upper water intake pipe and Ⅱ is the lower water intake pipe.

[0019] Explanation of reference numerals in the attached figures: 1. Upper reservoir; 2. First turbine unit; 3. First control valve; 4. Water-air co-containment chamber; 5. Second control valve; 6. Second water pump and turbine unit; 7. Lower reservoir; 8. Third control valve; 9. First water pump unit. Detailed Implementation

[0020] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0021] This invention proposes a pumped compressed air energy storage system based on pumped storage and a water pump and turbine, as described below. Figure 1 Please provide a detailed explanation.

[0022] A pumped compressed air energy storage system based on pumped storage and pumps and turbines includes an upper reservoir 1 and a lower reservoir 7, with an upper water intake pipe and a lower water intake pipe connecting the upper reservoir 1 and the lower reservoir 7. The upper water intake pipeline is sequentially connected to the first turbine unit 2, the water-air co-containment chamber 4, and the second water pump and turbine unit 6 along the direction from the upper reservoir 1 to the lower reservoir 7. A first control valve 3 is installed between the first turbine unit 2 and the water-air co-containment chamber 4, and the first control valve 3 is used to control the pipeline passage between the upper reservoir 1 and the water-air co-containment chamber 4. A second control valve 5 is installed between the water-air co-containment chamber 4 and the second water pump and turbine unit 6, and the second control valve 5 is used to control the pipeline passage between the lower reservoir 7 and the water-air co-containment chamber 4. A system recovery component is installed on the lower water intake pipe.

[0023] Compared with traditional physical energy storage technologies, this invention can simultaneously combine the advantages of high efficiency, high energy density and short construction cycle. At the same time, it can deeply reuse existing pumped storage power station infrastructure without adding new reservoirs and gas storage facilities. While increasing the installed capacity of the power station, it can significantly enhance the grid regulation flexibility and ensure the safe and stable operation of the power system.

[0024] Specifically, during the energy storage phase, the initial gas pressure in the water-gas co-containment chamber 4 is at the first pressure state. The first control valve 3 is opened, allowing water from the upper reservoir 1 to enter the water-gas co-containment chamber 4. The first turbine unit 2 generates electricity under the propulsion of the water flow. The water in the upper reservoir 1 compresses the gas in the water-gas co-containment chamber 4 for the first time, causing the pressure inside the chamber to rise for the first time. During this process, the pressure inside the water-gas co-containment chamber 4 is monitored in real time. When the pressure inside the chamber rises to the second pressure, the first control valve 3 is closed and the second control valve 5 is opened. The second water pump and the pump unit of the turbine unit 6 operate, pumping water from the lower reservoir 7 into the water-gas co-containment chamber 4. At this time, the gas inside the chamber is compressed for the second time. When the gas pressure is monitored to rise to the third pressure, the second control valve 5 is closed, and energy storage is completed. During the energy release phase, the second control valve 5 is opened, and the second water pump and turbine unit 6 operate. Water in the water-air coexistence chamber 4 flows through the turbine unit in the second water pump-turbine unit to generate electricity and release energy. The water level in the water-air coexistence chamber 4 is monitored in real time. When the water level reaches the dead water level, the second control valve 5 is closed, and energy release stops. The dead water level refers to the lowest safe position set during the energy release phase based on maintaining the minimum operating head of the turbine and preventing gas from entering the flow channel. In some embodiments, to detect the air pressure and water level in the water-air coexistence chamber 4, a pressure sensor is installed in the upper gas region of the chamber, and a level sensor is installed in the lower water region.

[0025] In some embodiments, the system recovery component includes a first water pump unit 9 installed on a lower water intake pipe. A third control valve 8 is installed on the lower water intake pipe between the first water pump unit 9 and the lower reservoir 7. The third control valve 8 is used to control the pipe passage between the lower reservoir 7 and the upper reservoir 1. When system recovery is performed, the first water pump unit 9 and the third control valve 8 are turned on to pump water from the lower reservoir 7 to the upper reservoir 1, so that the water level in the upper reservoir 1 reaches the water level at the initial moment of the energy storage stage, thereby resetting the entire system.

[0026] In some embodiments, the height difference between the upper reservoir 1 and the water-air co-containment chamber 4 H satisfy H ≥300m.

[0027] In some embodiments, the upper layer of the water-gas co-containment chamber 4 is high-pressure gas, and the lower layer is water.

[0028] The present invention also provides a method for pumped compressed air energy storage using any of the above systems, comprising: During the energy storage phase, the initial gas pressure in the water-gas co-containment chamber 4 is the first gas pressure state. The first control valve 3 is opened to allow water from the upper reservoir 1 to enter the water-gas co-containment chamber 4. During this process, the water in the upper reservoir 1 enters the water-gas co-containment chamber 4 after passing through the first turbine unit 2 under the action of gravity. While compressing the gas in the water-gas co-containment chamber 4, the water flow drives the first turbine unit 2 to generate electricity, converting the gravitational potential energy of the water flow into electrical energy. When water from the upper reservoir 1 enters the water-air co-containment chamber 4 until the air pressure inside the chamber rises to the second air pressure state, the first control valve 3 is closed and the second control valve 5 is opened. The second water pump and the water pump unit in the turbine unit 6 work to pump water from the lower reservoir 7 into the water-air co-containment chamber 4 until the air pressure inside the water-air co-containment chamber 4 rises to the third air pressure state, and then the second control valve 5 is closed. During the energy release phase, the second control valve 5 is opened, and the turbine unit in the second water pump and turbine unit 6 starts working. The water in the water-air co-containment chamber 4 enters the lower reservoir 7 after passing through the turbine unit in the second water pump turbine unit until the water level in the chamber gradually drops to the dead water level. Then, the second control valve 5 is closed. At this time, the air pressure in the water-air co-containment chamber 4 drops to the first air pressure state. The dead water level refers to the lowest safe position set by the water level in the water-air co-containment chamber during the energy release phase based on the requirements of maintaining the minimum operating head of the turbine and preventing gas from entering the flow channel.

[0029] During the recovery phase, the system recovery component pumps water from the lower reservoir 7 to the upper reservoir 1, restoring the water level of the upper reservoir 1 at the initial moment of the energy storage phase. Specifically, the third control valve 8 is opened, and the first pump unit 9 pumps water from the lower reservoir 7 to the upper reservoir 1, restoring the water level in the upper reservoir 1 to the initial moment of the energy storage phase, thus resetting the entire system.

[0030] In some embodiments, both the energy storage phase and the energy release phase are isothermal processes.

[0031] In some embodiments, the first air pressure < the second air pressure < the third air pressure; wherein: The pressure range of the first pressure state is 2-3 MPa; The pressure range of the second pressure state is 3-8 MPa; The pressure range of the third pressure state is 10-16 MPa.

[0032] In some embodiments, the system efficiency when using this method The calculation method is as follows: ; in, This represents the energy storage capacity of the energy storage system. This represents the power consumption of the energy storage system. System energy density Calculate using the following formula: ; in, It is a water-air co-containment chamber with a volume of 4.

[0033] Furthermore, the energy storage capacity of the energy storage system Calculate as follows: ; in, For the power generation of the first turbine unit 2, For the power generation of the second water pump and the turbine unit in turbine unit 6; The first turbine unit 2 generates electricity. The numerical calculation is as follows: ; in, The operating efficiency of the first turbine unit 2; V The total volume of water flowing through the first turbine unit 2 during the process of the gas in the water-gas co-containment chamber 4 rising from the first atmospheric pressure state to the second atmospheric pressure state; The density of the water body; h ( t () represents the first turbine unit with a head of 2. p up The water pressure inside Reservoir 1; p down ( t The pressure inside the water-air co-containment chamber 4 is 4. p 1 represents the pressure corresponding to the first pressure state of the gas in the water-air co-containment chamber 4; V 1 represents the gas volume in the water-air co-containment chamber 4 when the gas is in the first atmospheric pressure state; V ( t The total volume of water flowing into the water-air co-containment chamber 4 after passing through the first turbine unit 2. Power generation of the second water pump and turbine unit 6 when the turbine unit is operating Calculate using the following formula: ; in, The operating efficiency of the turbine unit in the second water pump turbine unit; p 2 represents the pressure corresponding to the third pressure state of the gas in the water-air co-containment chamber 4.

[0034] In some embodiments, the power consumption of the energy storage system Calculate as follows: ; in, The first water pump unit consumes 9 units of power. The power consumption of the second water pump and the water pump unit in turbine unit 6; The first water pump unit consumes 9 units of power. Calculate as follows: ; in, The operating efficiency of the first water pump unit 9; HThe height difference between the upper reservoir 1 and the water-air co-containment chamber 4; The power consumption of the second water pump and turbine unit 6 during operation Calculate using the following formula: ; in, The operating efficiency of the second water pump and turbine unit 6 when the water pump unit is working; V The volume of gas inside the water-air co-containment chamber 4; p 3 represents the pressure corresponding to the second pressure state of the gas in the water-air co-containment chamber 4.

[0035] In one embodiment, a set of specific implementation data is provided, and the system efficiency is verified by substituting it into the above calculation formula, as follows: The height difference between the upper reservoir 1 and the water-air co-containment chamber 4 H =500m, the volume of water-air co-containment chamber 4 is 24000m³. The pressure value corresponding to the gas in water-air co-containment chamber 4 when the gas is in the first atmospheric pressure state. p 1 is 3 MPa; considering the dead water level, the gas volume corresponding to the first atmospheric pressure state in the water-air co-containment chamber 4 is... V 1 is 23000 m 3 The pressure value corresponding to the second atmospheric pressure state of the gas in the water-air co-containment chamber 4, that is, the pressure caused by the elevation difference of the upper reservoir 1, is 5 MPa; the operating efficiency of the first turbine unit 2. It is 91%; Substituting the above values ​​into... W turbine1 The calculation formula yields the power generation of the first turbine unit 2. W turbine1 = 2.72 MW H ; The pressure value corresponding to the third pressure state of the gas in the water-air co-containment chamber 4 is 16 MPa. The operating efficiency of the second water pump and the turbine unit 6. It is 91%. Substituting the above values ​​into... W turbine2 The calculation formula can be used to obtain the power generation of the turbine unit in the second water pump turbine unit. W turbine2 = 29.20 MW H ; Depend on W storage The calculation formula yields the energy storage capacity of the energy storage system as follows: =31.92 MW H ; The operating efficiency of the first water pump unit 9 is 90%. Substituting the above values ​​into... Wpump1 The calculation formula yields the power consumption of the first water pump unit. W pump1 = 13.91 MW H ; The pump unit of the second water pump and turbine unit 6 has an operating efficiency of 90%. Substituting the above values ​​into... W pump2 The calculation formula can be used to obtain the power consumption of the second water pump unit. W pump2 = 24.77 MW H ; Depend on The calculation formula yields the following power consumption of the energy storage system: =38.68 MW H ; Pour the above data into the system efficiency. and the system's energy density From the calculation formula, we can obtain the system efficiency. The calculated result is 82.52%, system energy density. The calculated result is 1.3878 kW. H / m³.

[0036] In summary, this invention provides a pumped-storage compressed air energy storage system and method based on pumped-storage and pumps and turbines, achieving a system efficiency of over 80%. Compared to traditional physical energy storage technologies, it simultaneously offers the advantages of high efficiency, high energy density, and short construction period. It deeply reuses existing pumped-storage power station infrastructure, eliminating the need for new reservoirs and gas storage facilities. While increasing the installed capacity of the power station, it significantly enhances the grid's regulatory flexibility, ensuring the safe and stable operation of the power system.

[0037] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0038] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0039] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0040] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0041] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0042] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A method for pumped-air energy storage relying on pumped-air energy storage and pumps and turbines, characterized in that, The system includes an energy storage system, which comprises an upper reservoir and a lower reservoir, and the upper reservoir and the lower reservoir are connected by an upper water intake pipe and a lower water intake pipe. The upper water intake pipeline is sequentially connected to a first turbine unit, a water-air co-containment chamber, and a second water pump and turbine unit along the direction from the upper reservoir to the lower reservoir; a first control valve is provided between the first turbine unit and the water-air co-containment chamber, and a second control valve is provided between the water-air co-containment chamber and the second water pump and turbine unit; A system recovery component is installed on the lower water intake pipe; The energy storage method using the above energy storage system is as follows: During the energy storage phase, the initial gas pressure in the water-gas co-containment chamber is the first gas pressure state. The first control valve is opened to allow water from the upper reservoir to enter the water-gas co-containment chamber. During this process, the water flow drives the first turbine unit to generate electricity. When water from the upper reservoir enters the water-air co-containment chamber until the air pressure inside the chamber rises to the second air pressure state, the first control valve is closed and the second control valve is opened. The second water pump and the water pump unit in the turbine unit work to pump water from the lower reservoir into the water-air co-containment chamber until the air pressure in the water-air co-containment chamber rises to the third air pressure state, and then the second control valve is closed. During the energy release phase, the second control valve is opened, and the second water pump and the turbine unit in the turbine generator set operate. The water in the water-air coexistence chamber enters the lower reservoir after passing through the second water pump and the turbine unit in the turbine generator set. The water level in the chamber gradually drops to the dead water level, and then the second control valve is closed. At this time, the air pressure in the water-air coexistence chamber drops to the first air pressure state. The dead water level refers to the lowest safe position set by the water level in the water-air coexistence chamber during the energy release phase based on the requirements of maintaining the minimum operating head of the turbine and preventing gas from entering the flow channel. During the recovery phase, the water in the lower reservoir is pumped to the upper reservoir through the system recovery component to restore the initial water level of the upper reservoir during the energy storage phase.

2. The method for pumped-air energy storage based on pumped storage and a pump and turbine as described in claim 1, characterized in that, The system recovery component includes a first water pump unit installed on the lower water intake pipe, and a third control valve is installed on the lower water intake pipe between the first water pump unit and the lower reservoir.

3. The method for pumped-air energy storage based on pumped storage and a pump and turbine as described in claim 1, characterized in that, The height difference between the upper reservoir and the water-air co-containment chamber H satisfy H ≥300m.

4. The method for pumped-air energy storage based on pumped storage and a pump and turbine as described in claim 1, characterized in that, The upper layer of the water-gas co-containment chamber is high-pressure gas, and the lower layer is water.

5. The method for pumped-air energy storage based on pumped storage and a pump and turbine as described in claim 1, characterized in that, Both the energy storage stage and the energy release stage are isothermal processes.

6. The method for pumped-air energy storage based on pumped storage and a pump and turbine as described in claim 2, characterized in that, When using this method, the system efficiency is... The calculation method is as follows: ； in, This represents the energy storage capacity of the energy storage system. This represents the power consumption of the energy storage system. System energy density Calculate using the following formula: ； in, The volume of the water-air co-containment chamber.

7. The method for pumped-air energy storage based on pumped storage and a pump and turbine as described in claim 6, characterized in that, The energy storage capacity of the energy storage system Calculate as follows: ； in, This represents the power generation of the first turbine unit. The power generation of the second water pump and the turbine unit in the water turbine unit; Power generation of the first hydro-turbine unit The numerical calculation is as follows: ； in, The operating efficiency of the first turbine unit; V The total volume of water flowing through the first turbine unit during the process of the gas in the water-gas co-containment chamber rising from the first atmospheric pressure state to the second atmospheric pressure state; The density of the water body; h ( t The head of the first turbine unit is 1. p up The pressure of the water body inside the upper reservoir; p down ( t The pressure inside the water-air co-containment chamber is ). p 1 represents the pressure corresponding to the first pressure state of the gas in the water-gas co-containment chamber; V 1 represents the gas volume in the water-gas co-containment chamber when the gas is at the first atmospheric pressure. V ( t The total volume of water flowing into the water-air co-containment chamber after passing through the first turbine unit; The power generation of the second water pump and turbine unit when the turbine unit is operating Calculate using the following formula: ; in, The operating efficiency of the second water pump and the turbine unit in the water turbine unit; p 2 represents the pressure corresponding to the third pressure state of the gas in the water-gas co-containment chamber.

8. A method for pumped-air energy storage based on pumped storage and a pump and turbine, as described in claim 7, characterized in that, The power consumption of the energy storage system Calculate as follows: ； in, The power consumption of the first water pump unit. This refers to the power consumption of the pump unit in the second water pump and turbine unit; The first water pump unit consumes power Calculate as follows: ； in, The operating efficiency of the first water pump unit; H The height difference between the upper reservoir and the water-air co-containment chamber; The power consumption of the second water pump and turbine unit during pump unit operation Calculate using the following formula: ； in, The operating efficiency of the second water pump and the water pump unit in the turbine unit; p 3 represents the pressure corresponding to the second pressure state of the gas inside the water-gas co-containment chamber.

9. A method for pumped-air energy storage based on pumped storage and a pump and turbine, as described in any one of claims 6-8, characterized in that, The first air pressure < the second air pressure < the third air pressure; wherein: The pressure range of the first pressure state is 2-3 MPa; The pressure range of the second pressure state is 3-8 MPa; The pressure range of the third pressure state is 10-16 MPa.

Images