A bidirectional energy storage power generation system and power generation method based on compressed air unit

Abstract

The present application proposes a bidirectional energy storage power generation system and a power generation method based on a compressed air unit. By heat exchange connection between a heat storage component and an air storage component and realizing compressed air in the air storage component to pressurize the working fluid liquid in the first power generation component and the second power generation component, the stable operation of the bidirectional energy storage power generation system in the power generation process can be ensured, and the system has the advantages of low requirements for engineering geological conditions and high energy storage power generation efficiency. In addition, the first turbine unit and the second turbine unit arranged in the first power generation component and the second power generation component are forward and reverse turbine units, and the first high-pressure liquid storage tank and the second high-pressure liquid storage tank and the forward and reverse turbine units are connected, and the compressed air in the air storage component is used to pressurize the working fluid liquid in the first high-pressure liquid storage tank and the second high-pressure liquid storage tank to realize bidirectional power generation. In the power generation process, the air pressure in the first high-pressure liquid storage tank and the second high-pressure liquid storage tank is increased, so that the forward and reverse turbine units are always in the optimal efficiency range.

Description

Technical Field

[0001] The present application relates to the technical field of energy storage and power generation, and in particular to a bidirectional energy storage and power generation system and a power generation method based on a compressed air unit. Background Art

[0002] Energy is the material basis for human survival and development. In recent years, with the rapid increase in the consumption of fossil energy, the resulting problems such as conventional energy shortage and greenhouse gas emissions have become increasingly serious. Therefore, electricity is generated through new energy methods such as thermal energy, solar energy and wind energy, but there are problems such as a relatively single power generation method and low efficiency. In recent years, in order to cope with the challenging problems caused by the consumption of fossil fuels and the impact of environmental factors on new energy, new energy storage and power generation technologies have begun to be vigorously developed, such as compressed air energy storage power generation and electromagnetic energy storage power generation. At present, for the relatively mature compressed air energy storage technology, there are also certain limitations. For example, when compressed air energy storage releases air, the pressure is unstable, the utilization rate is low, and the application scenarios and promotion and application value directly affect the efficiency and economy of the power generation system. Therefore, it is urgent to develop a new pumped storage power generation system based on compressed air technology to maximize the utilization of stored energy and ensure the stability and efficiency of the system, and it is very easy to promote and apply.

[0003] Prior art CN114777233A discloses a pumped cold and heat storage power station, including a hydroelectric generator set, an upper reservoir, a lower reservoir, and a heat pump unit. During pumping and storage at night, the hydroelectric generator set pumps water from the lower reservoir to the upper reservoir. During the peak of electricity consumption during the day, the water in the upper reservoir is released to the lower reservoir to drive the hydroelectric generator set to generate electricity, which plays a role in eliminating peaks and filling valleys in the operation of the power grid. Although the patent of this invention has well tapped the potential of water bodies to store thermal energy, it is only applicable to construction in mountainous areas and has strict restrictions on geographical and topographical conditions. The upper and lower reservoirs must have a sufficiently high drop to be feasible, and the system is complex and requires large investment, so its application and promotion value is limited. In addition, CN102619668A discloses a constant pressure water-gas co-containment cabin power energy storage system, including a water-gas co-containment cabin, a gas compressor unit, a water pump unit, a water storage tank, and a turbine. The gas compressor and water pump unit work by utilizing the surplus electric energy of the power grid. The water pump unit draws water from the water tank through a pipeline. The outlet of the gas compressor unit is connected to the water-gas co-containment tank through a valve and a pipeline. The outlet of the water-gas co-containment tank is connected to the turbine through a pipeline and a valve. The turbine drives the generator to generate electricity and output electricity. Although it can improve the utilization rate of existing energy and provide new ideas for the research of compressed air energy storage cycle system, there are still some disadvantages: the steam boiler consumes non-renewable resources to produce steam, and greenhouse gas emissions may increase sharply, which is not conducive to energy conservation and emission reduction. In addition, the system has a complex structure and cannot guarantee the efficiency and stability of the energy storage power generation system. Summary of the invention

[0004] The present application aims to solve one of the technical problems in the related art at least to some extent.

[0005] To this end, the purpose of the present application is to propose a bidirectional energy storage power generation system and a power generation method based on a compressed air unit, which can ensure the stable operation of the bidirectional energy storage power generation system during the power generation process and can also place the liquid storage component at any height. It has the advantages of low requirements for engineering geological conditions and high energy storage power generation efficiency. In addition, the first turbine group and the second turbine group arranged in the first power generation component and the second power generation component are forward and reverse turbine groups, through which the first The high-pressure liquid storage tank is connected to the second high-pressure liquid storage tank and the forward and reverse water turbine sets, and the compressed air in the gas storage member is used to pressurize the working fluid in the first high-pressure liquid storage tank and the second high-pressure liquid storage tank to achieve bidirectional power generation; at the same time, during the power generation process, as the liquid level of the working fluid in the first high-pressure liquid storage tank and the second high-pressure liquid storage tank decreases, the air pressure in the first high-pressure liquid storage tank and the second high-pressure liquid storage tank is increased, so that the forward and reverse water turbine sets are always in the optimal efficiency range, and after the unidirectional power generation is completed, the heat energy collected by the heat storage member during the energy storage process is fully utilized for heating and pressure compensation of the gas storage member in the power generation link.

[0006] In order to achieve the above-mentioned purpose, the present application proposes a bidirectional energy storage power generation system based on a compressed air unit, comprising:

[0007] A compressed air unit, comprising an air compression assembly and at least one air storage member; wherein the air storage member is connected to the air compression assembly, and the air storage member is used to store compressed air generated by the air compression assembly;

[0008] A liquid heat storage unit, comprising a liquid storage component and a heat storage component which are interconnected, both containing a working fluid; wherein the heat storage component is heat-exchange connected to the air compression component and the gas storage component, respectively, and stores the compression heat generated by the air compression component and provides heat to the gas storage component; and

[0009] A bidirectional energy storage power generation unit comprises a first power generation component and a second power generation component; wherein the first power generation component and the second power generation component are respectively connected to the liquid storage component and the air storage component, and the working fluid in the first power generation component and the second power generation component circulate with each other, wherein the input compressed air drives the stored working fluid to flow toward each other to realize bidirectional power generation and work.

[0010] In some embodiments, a back-pressure passage is also included, and the back-pressure passage includes a first back-pressure passage connecting the first power generation component and the heat storage component and a second back-pressure passage connecting the second power generation component and the heat storage component; the first back-pressure passage and the second back-pressure passage are used to recover the compressed air in the first power generation component and the second power generation component respectively and pass them into the air storage component after heat exchange with the heat storage component.

[0011] In some embodiments, the first power generation component includes a first high-pressure liquid storage component and a second turbine unit; wherein the liquid inlet of the first high-pressure liquid storage component is connected to the liquid storage component, and its air inlet is connected to the air storage component through a first air pipeline, and the liquid outlet of the first high-pressure liquid storage component is connected to the liquid inlet of the second turbine unit; the liquid outlet of the second turbine unit is connected to the second power generation component.

[0012] In some embodiments, the first power generation component further includes a first water-gas separator, a first pressure stabilizer, and a first pressure relief valve which are sequentially arranged on the first gas transmission pipeline according to the gas transmission direction.

[0013] In some embodiments, a pressure sensor is disposed on the first pressure relief valve.

[0014] In some embodiments, a sixth regulating valve, a fifth regulating valve and a second regulating valve are respectively provided on the first gas transmission pipeline, between the liquid outlet of the second turbine unit and the second power generation assembly, and between the liquid inlet of the first high-pressure liquid storage assembly and the liquid storage member.

[0015] In some embodiments, a first pressure regulating well is disposed between the second regulating valve and the first high-pressure liquid storage assembly.

[0016] In some embodiments, the second power generation component includes a second high-pressure liquid storage component and a first turbine unit; wherein the liquid inlet of the second high-pressure liquid storage component is connected to the liquid outlet of the second turbine unit, and its air inlet is connected to the air storage component through a second air pipeline, and the liquid outlet of the second high-pressure liquid storage component is respectively connected to the liquid inlet of the first turbine unit and the liquid storage component; the liquid outlet of the first turbine unit is connected to the liquid inlet of the second high-pressure liquid storage component.

[0017] In some embodiments, the second power generation assembly further includes a second water-gas separator, a second pressure stabilizer and a second pressure relief valve which are sequentially arranged on the second gas transmission pipeline according to the gas transmission direction.

[0018] In some embodiments, a pressure sensor is disposed on the second pressure relief valve.

[0019] In some embodiments, a first regulating valve, a fourth regulating valve and a third regulating valve are respectively arranged on the second gas transmission pipeline, between the liquid outlet of the first turbine unit and the first high-pressure liquid storage assembly, and between the second high-pressure liquid storage assembly and the liquid storage member.

[0020] In some embodiments, a second pressure regulating well is provided between the third regulating valve and the second high-pressure liquid storage assembly.

[0021] According to another object of the present application, a bidirectional energy storage and power generation method based on a compressed air unit is proposed, which generates electricity using the power generation system described in any of the above embodiments.

[0022] In some embodiments, the following process is included:

[0023] Energy storage stage: the air compression component compresses the input air and stores the generated compressed air in the air storage component after exchanging heat with the working fluid liquid in the heat storage component;

[0024] Power generation stage: including the power generation process of the first power generation component and the power generation process of the second power generation component;

[0025] The power generation process of the first power generation assembly: in the initial stage, the first high-pressure liquid storage assembly is filled with working fluid, and the second high-pressure liquid storage assembly is empty; the second gas pipeline is opened to pre-pressurize the second high-pressure liquid storage assembly until the pressure of the second high-pressure liquid storage assembly is balanced with that of the first high-pressure liquid storage assembly, and then the second gas pipeline is closed;

[0026] The second regulating valve and the third regulating valve are closed, and the first gas transmission pipeline, the second back pressure passage and the fifth regulating valve are opened. The working fluid in the first high-pressure liquid storage assembly enters the second turbine unit under the set pressure and then flows into the second high-pressure liquid storage assembly to perform work, so that the operation of the second turbine unit is stably maintained at the optimal working condition; at the same time, the compressed air in the second high-pressure liquid storage assembly is passed into the gas storage component after heat exchange and temperature increase with the heat storage component through the second back pressure passage; the fifth regulating valve is closed until all the working fluid enters the second high-pressure liquid storage assembly, and the air pressure in the second high-pressure liquid storage assembly is balanced;

[0027] The power generation process of the second power generation component: close the second regulating valve and the third regulating valve and open the second gas pipeline, the first back pressure passage and the fourth regulating valve; the working fluid in the second high-pressure liquid storage component enters the first turbine unit under the set pressure to perform work and then flows into the first high-pressure liquid storage component, so that the operation of the first turbine unit is stably maintained at the optimal working condition; at the same time, the compressed air in the first high-pressure liquid storage component passes through the first back pressure passage and is heated and heated by the heat storage component before being passed into the gas storage component; until all the working fluid enters the first high-pressure liquid storage component, the air pressure in the first high-pressure liquid storage component is balanced.

[0028] In some embodiments, when the first water turbine unit and the second water turbine unit are maintained at the optimal working condition, their working water heads remain unchanged and can be expressed as:

[0029] H=H z +H p

[0030] The operating characteristic curve formula is:

[0031] η=f(P,H)

[0032] P=η t γQH=9.81η t QH

[0033]

[0034]

[0035] Where: η is the turbine efficiency; P is the output, kW; η t is the model efficiency; γ is the bulk density, kN / m 3 , 9.81 is the acceleration due to gravity, m / s 2 ; H is the head, m; Q is the flow, m 3 / s;n 11 It represents the rotation speed of a geometrically similar turbine when the runner diameter is 1m and the effective water head is 1m, m / s; Q 11 It represents the effective flow rate when the geometrically similar turbine has a runner diameter of 1m and an effective head of 1m, m 3 / s; n is the rotation speed, m / s; D 1 is the nominal diameter of the runner, m.

[0036] In some embodiments, the power generation stage also includes, during the power generation process of the first power generation component, after all the working fluid enters the second high-pressure liquid storage component, closing the second back-pressure passage and the first gas pipeline, opening the first back-pressure passage, and utilizing the compressed air in the first high-pressure liquid storage component to exchange heat with the heat storage component through the first back-pressure passage and then pass it into the gas storage component until the air pressure in the first high-pressure liquid storage component is the same as the hydraulic pressure in the second high-pressure liquid storage tank.

[0037] In some embodiments, the power generation stage also includes, during the power generation process of the second power generation component, after all the working fluid enters the first high-pressure liquid storage component, closing the first back-pressure passage and the second gas pipeline, opening the second back-pressure passage, and utilizing the compressed air in the second high-pressure liquid storage component to exchange heat with the heat storage component through the second back-pressure passage and then pass into the gas storage component until the air pressure in the second high-pressure liquid storage component is the same as the hydraulic pressure in the first high-pressure liquid storage tank.

[0038] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0040] Figure 1 It is a structural block diagram of a bidirectional energy storage and power generation system based on a compressed air unit proposed in one embodiment of the present application;

[0041] Figure 2 It is a structural schematic diagram of a bidirectional energy storage and power generation system based on a compressed air unit proposed in one embodiment of the present application;

[0042] Figure 3 is a schematic structural diagram of a first high-pressure liquid storage assembly and a second high-pressure liquid storage assembly proposed in an embodiment of the present application;

[0043] Figure 4 is a working range diagram of the first water turbine unit and the second water turbine unit proposed in one embodiment of the present application;

[0044] Figure 5 is a curve showing the relationship between the output and the water head of the first water turbine unit and the second water turbine unit proposed in one embodiment of the present application;

[0045] In the figure, 1, liquid storage component; 2, first high-pressure liquid storage component; 3, second high-pressure liquid storage component; 4, heat storage component; 50, gas storage component; 5, first gas storage tank; 6, second gas storage tank; 7, third gas storage tank; 8, air compression component; 9, first heat exchanger; 10, second heat exchanger; 11, first pressure stabilizer; 12, second pressure stabilizer; 13, first turbine unit; 14, second turbine unit; 15, first water-gas separator; 16, first pressure regulating well; 17, second pressure regulating well; 18, first pressure relief valve; 19, second pressure relief valve; 20, first regulating valve; 21, second regulating valve; 22, third regulating valve; 23, fourth regulating valve; 24, fifth regulating valve; 25, sixth regulating valve; 26, seventh regulating valve; 27, eighth regulating valve; 28, second water-gas separator; 29, ninth regulating valve. DETAILED DESCRIPTION

[0046] Embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and cannot be construed as limiting the present application. On the contrary, the embodiments of the present application include all changes, modifications and equivalents that fall within the spirit and connotation of the appended claims.

[0047] See also Figure 1 To achieve the above objectives, the present application proposes a bidirectional energy storage power generation system based on a compressed air unit, such as Figure 1 The figure shows a compressed air unit, a liquid heat storage unit and a bidirectional energy storage power generation unit; wherein the compressed air unit includes an air compression component 8 and at least one air storage component 50, and the air storage component 50 is connected to the air compression component 8 and is used to store the compressed air generated by the air compression component 8; in other words, the compressed air unit includes an air compression component 8 and an air storage component 50 or two or more air storage components 50; wherein the air compression component 8 in this embodiment is used to compress air and generate compressed air, and the compressed air is passed into the air storage component 50 for storage.

[0048] For example, Figure 2 The compressed air unit shown includes an air compression component 8 and three air storage components 50, wherein the air compression component 8 can be understood as a multi-stage series-connected air compressor, wherein air is introduced into the gas inlet of the air compressor, and compressed air is generated after being compressed by the air compressor; the gas outlet of the air compressor is respectively connected to the three air storage components 50; it can be known that the air storage components 50 can be air storage tanks, each of which is provided with a gas inlet and a gas outlet; in the present embodiment, the three air storage components 50 are respectively a first air storage tank 5, a second air storage tank 6 and a third air storage tank 7, wherein the inlets of the three air storage tanks are all connected to the gas outlet of the air compressor for storing compressed air, and the outlets of the three air storage tanks are all connected to the bidirectional energy storage power generation unit for pressurizing the bidirectional energy storage power generation unit to perform work.

[0049] The liquid heat storage unit includes a liquid storage component 1 and a heat storage component 4 which are interconnected, both of which contain a working fluid, and the working fluid is exemplified as water; wherein the heat storage component 4 is respectively connected to the air compression component 8 and the gas storage component 50 for heat exchange, and stores the compression heat generated by the air compression component 8 and provides heat to the gas storage component 50; in other words, the liquid heat storage unit includes a liquid storage component 1 and a heat storage component 4, wherein both the liquid storage component 1 and the heat storage component 4 contain a certain volume of working fluid, and the working fluid between the two can flow mutually. For example, Figure 2As shown, the liquid storage component 1 can be understood as a liquid storage tank, and its volume is much larger than that of the heat storage component 4. The liquid storage component 1 can be arranged above the heat storage component 4. In most working conditions of the bidirectional energy storage power generation system, the working fluid in the liquid storage component 1 flows into the heat storage component 4 in a single direction. In very rare cases, the working fluid in the heat storage component 4 needs to flow into the heat storage component 4. Therefore, the liquid storage component 1 can be arranged above the heat storage component 4, and a seventh regulating valve 26 is provided on the pipeline connecting the liquid storage component 1 and the heat storage component 4, so that the working fluid in the liquid storage component 1 can flow into the heat storage component 4 by its own gravity. As for the working fluid in the heat storage component 4 flowing into the heat storage component 4, it can be achieved by a liquid pump and will not be repeated.

[0050] In this embodiment, the heat storage component 4 is connected to the air compression component 8 and the air storage component 50 for heat exchange, and stores the compression heat generated by the air compression component 8 and provides heat to the air storage component 50. It is understandable that in the compressed air energy storage system in the related technology, up to 85% of the electrical energy is converted into thermal energy during the air compression process, and the air potential energy conversion efficiency is extremely low. The heat carried by the high-temperature and high-pressure oil and gas in the thermal energy is approximately equivalent to 85% of the power consumption of the air compressor. This is recoverable heat. The air compression component 8 will generate a large amount of heat during the air compression process. The heat of the compressed air can be collected by setting a heat exchanger and stored in the heat storage component 4. For example, Figure 2 As shown, a first heat exchanger 9 is arranged between the air compression assembly 8 and the heat storage element 4, wherein the first heat exchanger 9 includes a hot side and a cold side; compressed air is introduced into the hot side of the first heat exchanger 9, and the working fluid in the heat storage element 4 is introduced into the cold side thereof, and after the working fluid absorbs the heat of the compressed air, the cooled compressed air enters the air storage element 50, and the working fluid after absorbing the heat flows back to the heat storage element 4. In this embodiment, the high specific heat capacity of water is used, and the heat storage element 4 is arranged to store the heat generated during the air compression process to realize the heat recovery and utilization.

[0051] Similarly, a second heat exchanger 10 is arranged between the heat storage member 4 and the gas storage member 50, wherein the second heat exchanger 10 includes a hot side and a cold side; the working fluid in the heat storage member 4 is introduced into the hot side of the second heat exchanger 10, and the compressed air is introduced into the cold side thereof, and the heated compressed air is introduced into the gas storage member 50 to increase the pressure therein. When the compressed air in the gas storage member 50 is released, the air pressure in the gas storage member 50 will decrease, and the heat storage member 4 is used to supplement the heat to the gas storage member 50, further increasing the air pressure, thereby ensuring the high efficiency and stability of the bidirectional energy storage power generation system when it is in the working power generation condition.

[0052] The bidirectional energy storage power generation unit includes a first power generation component and a second power generation component; wherein the first power generation component and the second power generation component are respectively connected to the liquid storage component 1 and the gas storage component 50, and the compressed air input into the first power generation component and the second power generation component drives the mutually circulating working fluid to generate electricity and do work. In other words, the first power generation component is respectively connected to the liquid storage component 1 and the gas storage component 50, which can be understood as the first power generation component is connected to the liquid storage component 1, that is, the working fluid in the liquid storage component 1 is connected to the working fluid in the first power generation component; the first power generation component is in communication with the gas storage component 50, that is, the compressed air in the gas storage component 50 is in communication with the compressed air in the first power generation component; the second power generation component is respectively connected to the liquid storage component 1 and the gas storage component 50, which can be understood as the above and will not be repeated.

[0053] As for the mutual circulation of the working fluid liquid in the first power generation component and the second power generation component in this embodiment, that is, compressed air is input into the first power generation component or the second power generation component through the air storage component 50 to pressurize the working fluid liquid therein, and the working fluid liquid in the first power generation component or the second power generation component flows into each other to achieve work. In this embodiment, the first power generation component and the second power generation component can realize bidirectional energy storage power generation through the mutual circulation of working fluid liquid, and also make full use of the huge liquid storage space of the liquid storage component 1, thereby reducing the volume of the first power generation component and the second power generation component. In addition, during the power generation process of the bidirectional energy storage power generation system, as the water level in the liquid storage component 1 decreases, the air pressure in the first power generation component and the second power generation component is increased, so that the first power generation component and the second power generation component are always in the optimal efficiency range.

[0054] In some embodiments, a back-pressure passage is also included, and the back-pressure passage includes a first back-pressure passage connecting the first power generation component and the heat storage component 4 and a second back-pressure passage connecting the second power generation component and the heat storage component 4; the first back-pressure passage and the second back-pressure passage are used to recover the compressed air in the first power generation component and the second power generation component respectively and pass them into the heat storage component 4 after heat exchange with the heat storage component 4.

[0055] For example, the bidirectional energy storage power generation system also includes a back-pressure passage, and the back-pressure passage includes a first back-pressure passage connecting the first power generation component and the heat storage component 4 and a second back-pressure passage connecting the second power generation component and the heat storage component 4. In other words, the back-pressure passage includes a first back-pressure passage and a second back-pressure passage, and the first back-pressure passage is arranged between the first power generation component and the heat storage component 4, and is used to pass the compressed air in the first power generation component into the heat storage component 4 after heat exchange with the heat storage component 4; the second back-pressure passage is arranged between the second power generation component and the heat storage component 4, and is used to pass the compressed air in the second power generation component into the heat storage component 4 after heat exchange with the heat storage component 4. In some embodiments, an eighth regulating valve 27 and a ninth regulating valve 29 are respectively arranged on the first back-pressure passage and the second back-pressure passage, and the eighth regulating valve 27 and the ninth regulating valve 29 are used to regulate the flow rate of compressed air on the first back-pressure passage and the second back-pressure passage.

[0056] In some embodiments, the first power generation component includes a first high-pressure liquid storage component 2 and a second turbine unit 14; wherein the liquid inlet of the first high-pressure liquid storage component 2 is connected to the liquid storage component 1, and its air inlet is connected to the air storage component 50 through a first air pipeline, and the liquid outlet of the first high-pressure liquid storage component 2 is connected to the liquid inlet of the second turbine unit 14; the liquid outlet of the second turbine unit 14 is connected to the second power generation component.

[0057] The first high-pressure liquid storage assembly 2 includes at least one first high-pressure liquid storage tank; the first high-pressure liquid storage tank is a high-pressure, high-strength, sealed container that can simultaneously contain compressed air and working fluid. For example, Figure 2 The first high-pressure liquid storage assembly 2 shown includes a first high-pressure liquid storage tank, wherein the first high-pressure liquid storage tank has a first liquid inlet, a second liquid inlet, an air inlet, an air outlet and a liquid outlet; wherein the first liquid inlet of the first high-pressure liquid storage tank is connected to the liquid storage component 1, and the working fluid in the liquid storage component 1 can be input through the first liquid inlet of the first high-pressure liquid storage tank. In some schemes, a second regulating valve 21 is provided between the liquid storage component 1 and the first high-pressure liquid storage tank to regulate the flux of the working fluid between the two. Similarly, the air inlet of the first high-pressure liquid storage tank is connected to the air storage component 50 through the first air transmission pipeline, and the compressed air in the air storage component 50 can be passed into the air inlet of the first high-pressure liquid storage tank through the first air transmission pipeline; the second liquid outlet of the first high-pressure liquid storage tank is connected to the liquid inlet of the second turbine unit 14, that is, the working fluid in the first high-pressure liquid storage tank enters the second turbine unit 14 through its second liquid outlet to generate power; the air outlet of the first high-pressure liquid storage tank is connected to the first back pressure passage. After power generation, the working fluid flowing out of the second turbine unit 14 enters the second power generation assembly, realizing the circulation of the working fluid between the first power generation assembly and the second power generation assembly. The liquid outlet of the second turbine unit 14 is connected to the second power generation assembly, and a fifth regulating valve 24 is arranged between the two to regulate the flow of the working fluid entering the second power generation assembly.

[0058] In some embodiments, Figure 3 The first high-pressure liquid storage assembly 2 shown includes three first high-pressure liquid storage tanks connected in parallel, wherein the liquid outlets of the three first high-pressure liquid storage tanks are all connected to the liquid inlet of the second turbine unit 14; the first liquid inlets of the three first high-pressure liquid storage tanks are all connected to the liquid storage component 1, that is, the working fluid in the three first high-pressure liquid storage tanks enters the second turbine unit 14 through its second liquid outlet to perform work and generate electricity, which is consistent with the above and will not be repeated.

[0059] In some embodiments, the first power generation assembly further includes a first water-gas separator 15, a first pressure stabilizer 11 and a first pressure relief valve 18 which are sequentially arranged on the first gas transmission pipeline according to the gas transmission direction.

[0060] For example, the first power generation component also includes a first water-gas separator 15, a first pressure stabilizer 11 and a first pressure relief valve 18; wherein the first water-gas separator 15, the first pressure stabilizer 11 and the first pressure relief valve 18 are sequentially arranged on the first gas transmission pipeline according to the gas transmission direction, i.e., the flow direction of the compressed air in the gas storage component 50 to the first power generation component. The first water-gas separator 15 is used to separate the compressed air flowing out of the gas storage component 50 into gas and liquid, and the separated compressed air continues to flow in the first gas transmission pipeline; the first pressure stabilizer 11 can be a first intelligent pressure stabilizing device, which is used to stabilize the water head in the first high-pressure liquid storage tank to ensure that the second turbine unit 14 is in the optimal power range; the first pressure relief valve 18 is arranged on the air inlet of the first high-pressure liquid storage tank, which can be used to reduce the pressure in the first high-pressure liquid storage tank. In some schemes, a pressure sensor is arranged on the first pressure relief valve 18, and the pressure sensor can detect the pressure in the first high-pressure liquid storage tank, and adjust the pressure in the first high-pressure liquid storage tank by using the first pressure relief valve 18 according to the pressure in the first high-pressure liquid storage tank. In this embodiment, a sixth regulating valve 25 is further provided on the first gas transmission pipeline, wherein the sixth regulating valve 25 can be provided between the first water-gas separator 15 and the first pressure stabilizer 11 to adjust the flow rate of compressed air entering the first pressure stabilizer 11 .

[0061] In some embodiments, a first pressure regulating well 16 is provided between the second regulating valve 21 and the first high-pressure liquid storage assembly 2, wherein the first pressure regulating well 16 is used to balance the initial pressure of the first high-pressure liquid storage tank and pre-pressurize the first high-pressure liquid storage tank.

[0062] In some embodiments, the second power generation component includes a second high-pressure liquid storage component 3 and a first turbine unit 13; wherein the liquid inlet of the second high-pressure liquid storage component 3 is connected to the liquid outlet of the second turbine unit 14, and its air inlet is connected to the air storage component 50 through a second air pipeline, and the liquid outlet of the second high-pressure liquid storage component 3 is respectively connected to the liquid inlet and liquid storage component 1 of the first turbine unit 13; the liquid outlet of the first turbine unit 13 is connected to the liquid inlet of the first high-pressure liquid storage component 2.

[0063] The second high-pressure liquid storage assembly 3 includes at least one second high-pressure liquid storage tank; the second high-pressure liquid storage tank is a high-pressure, high-strength, sealed container that can simultaneously contain compressed air and working fluid. For example, Figure 2The second high-pressure liquid storage assembly 3 shown includes a second high-pressure liquid storage tank, wherein the second high-pressure liquid storage tank has a liquid inlet, an air inlet, a first liquid outlet, an air outlet and a second liquid outlet; wherein the first liquid outlet of the second high-pressure liquid storage tank is connected to the liquid storage component 1, and is used to input the working fluid therein into the liquid storage component 1. In some schemes, a third regulating valve 22 is provided between the liquid storage component 1 and the second high-pressure liquid storage tank, and is used to regulate the flux of the working fluid therebetween. The air inlet of the second high-pressure liquid storage tank is connected to the air storage component 50 through the second air supply pipeline, and the compressed air in the air storage component 50 can be passed into the air inlet of the second high-pressure liquid storage tank through the second air supply pipeline; the air outlet of the second high-pressure liquid storage tank is connected to the second back pressure passage; the second liquid outlet of the second high-pressure liquid storage tank is connected to the liquid inlet of the first turbine unit 13, that is, the working fluid in the second high-pressure liquid storage tank enters the first turbine unit 13 through its second liquid outlet to generate power. After power generation, the working fluid flowing out of the first turbine unit 13 enters the first power generation assembly. The liquid outlet of the first turbine unit 13 is connected to the second power generation assembly, and a fourth regulating valve 23 is arranged between the two to adjust the flow of the working fluid entering the first power generation assembly.

[0064] In some embodiments, Figure 3 The second high-pressure liquid storage assembly 3 shown includes three second high-pressure liquid storage tanks connected in parallel, wherein the first liquid outlets of the three second high-pressure liquid storage tanks are all connected to the liquid inlet of the first turbine unit 13; the second liquid outlets of the three second high-pressure liquid storage tanks are all connected to the liquid storage component 1, that is, the working fluid in the three second high-pressure liquid storage tanks enters the first turbine unit 13 through its second liquid outlet to perform work and generate electricity, which is consistent with the above and will not be repeated.

[0065] In some embodiments, the second power generation assembly further includes a second water-gas separator 28, a second pressure stabilizer 12 and a second pressure relief valve 19 which are sequentially arranged on the second gas transmission pipeline according to the gas transmission direction.

[0066] For example, the second power generation component also includes a second water-gas separator 28, a second pressure stabilizer 12 and a second pressure relief valve 19; wherein the second water-gas separator 28, the second pressure stabilizer 12 and the second pressure relief valve 19 are sequentially arranged on the second gas transmission pipeline according to the gas transmission direction, i.e., the flow direction of the compressed air in the gas storage component 50 to the second power generation component. The second water-gas separator 28 is used to separate the compressed air flowing out of the gas storage component 50 into gas and liquid, and the separated compressed air continues to flow in the second gas transmission pipeline; the second pressure stabilizer 12 can be a second intelligent pressure stabilizing device, which is used to keep the pressure of the compressed air passing through constant; the second pressure relief valve 19 is arranged on the air inlet of the second high-pressure liquid storage tank, which can be used to reduce the pressure in the second high-pressure liquid storage tank. In some schemes, a pressure sensor is arranged on the second pressure relief valve 19, and the pressure sensor can detect the pressure in the second high-pressure liquid storage tank, and adjust the pressure in the second high-pressure liquid storage tank by using the second pressure relief valve 19 according to the pressure in the second high-pressure liquid storage tank. In this embodiment, a first regulating valve 20 is further provided on the second gas transmission pipeline, wherein the first regulating valve 20 can be provided between the second water-gas separator 28 and the second pressure stabilizer 12 to adjust the flow rate of compressed air entering the second pressure stabilizer 12 .

[0067] In some embodiments, a second pressure regulating well 17 is disposed between the third regulating valve 22 and the second high-pressure liquid storage assembly 3, wherein the second pressure regulating well 17 is used to adjust the pressure of the working fluid flowing out of the second high-pressure liquid storage tank.

[0068] In some embodiments, a bidirectional energy storage and power generation method based on a compressed air unit is proposed, and power generation is performed using the power generation system in any of the above embodiments.

[0069] In some embodiments, the following process is included:

[0070] Energy storage stage: the air compression component 8 compresses the input air and exchanges heat between the generated compressed air and the working fluid in the heat storage component 4, and then stores the compressed air in the air storage component 50;

[0071] Power generation stage: including the power generation process of the first power generation component and the power generation process of the second power generation component;

[0072] The power generation process of the first power generation assembly: in the initial stage, the first high-pressure liquid storage assembly 2 is filled with working fluid, and the second high-pressure liquid storage assembly 3 is empty; the second gas pipeline is opened to pre-pressurize the second high-pressure liquid storage assembly 3 until the pressure of the second high-pressure liquid storage assembly 3 is balanced with that of the first high-pressure liquid storage assembly 2, and then the second gas pipeline is closed;

[0073] Close the second regulating valve 21 and the third regulating valve 22 and open the first gas pipeline, the second back pressure passage and the fifth regulating valve 24. The working fluid in the first high-pressure liquid storage assembly 2 enters the second turbine unit 14 under the set pressure to perform work and then flows into the second high-pressure liquid storage assembly 3, so that the operation of the second turbine unit 14 is stable and maintained at the optimal working condition; at the same time, the compressed air in the second high-pressure liquid storage assembly 3 passes through the second back pressure passage and exchanges heat with the heat storage component 4 and then enters the gas storage component 50; until all the working fluid enters the second high-pressure liquid storage assembly 3, the fifth regulating valve 24 is closed and the air pressure in the second high-pressure liquid storage assembly 3 is balanced;

[0074] The power generation process of the second power generation component is as follows: the second regulating valve 21 and the third regulating valve 22 are closed, and the second gas pipeline, the first back pressure passage and the fourth regulating valve 23 are opened. The working fluid in the second high-pressure liquid storage component 3 enters the first turbine unit 13 under the set pressure to perform work and then flows into the first high-pressure liquid storage component 2, so that the operation of the first turbine unit 13 is stably maintained at the optimal working condition; at the same time, the compressed air in the first high-pressure liquid storage component 2 passes through the first back pressure passage and exchanges heat with the heat storage component 4 and then enters the gas storage component 50; until all the working fluid enters the first high-pressure liquid storage component 2, the air pressure in the first high-pressure liquid storage component 2 is balanced.

[0075] Specifically, when the power supply side needs to generate electricity, the gas storage part 50 is filled with compressed air, the first high-pressure liquid storage tank is filled with working fluid, and the second high-pressure liquid storage tank is empty, and there is no compressed air or working fluid in it. When the first power generation component generates electricity: close the second regulating valve 21 and the third regulating valve 22 and open the first regulating valve 20 to open the second gas transmission pipeline, and use the high-pressure air in the gas storage part 50 to pre-pressurize the second high-pressure liquid storage tank so that the second high-pressure liquid storage tank and the first high-pressure liquid storage tank maintain the same hydraulic pressure, which can be measured through the first pressure regulating well 16 and the second pressure regulating well 17 until the pressure of the second high-pressure liquid storage tank and the first high-pressure liquid storage tank is balanced and then the first regulating valve 20 is closed. The second high-pressure liquid storage tank and the first high-pressure liquid storage tank maintain the same hydraulic pressure, which is conducive to the second turbine unit 14 maintaining stable work and preventing the working fluid from entering the second turbine unit 14 at a high pressure in the initial stage of the second turbine unit 14.

[0076] The sixth regulating valve 25 is opened, that is, the first gas transmission pipeline is opened, and the ninth regulating valve 29 is opened to open the second back pressure passage and the fifth regulating valve 24. The working fluid in the first high-pressure liquid storage tank enters the second turbine unit 14 under the set pressure to do work and then flows into the second high-pressure liquid storage tank, so that the operation of the second turbine unit 14 is stably maintained at the optimal working condition. If the working fluid is water, the operation of the second turbine unit 14 is stably maintained at the optimal working condition when the head is about 700m. As the liquid level in the second high-pressure liquid storage tank continues to increase, the air pressure in it continues to increase on the basis of pre-pressure. The compressed air in the second high-pressure liquid storage tank due to pre-pressurization is raised due to the water level in the second high-pressure liquid storage tank, and exchanges heat with the working fluid in the heat storage element 4 in the second heat exchanger 10 through the second back pressure passage. The compressed air after heat exchange is passed into the gas storage element 50 to increase the gas pressure in the gas storage element 50, so as to increase the heat and pressure of the gas storage element 50 during the power generation process and maintain the stable operation of the second turbine unit 14. Until all the working fluid enters the second high-pressure liquid storage tank, at which time the second high-pressure liquid storage tank is completely filled with compressed air, close the fifth regulating valve 24, and finally open the second pressure relief valve 19 to balance the air pressure inside the second high-pressure liquid storage tank, and then close the second pressure relief valve 19 and the ninth regulating valve 29.

[0077] The eighth regulating valve 27 is opened, and the compressed air in the first high-pressure liquid storage tank passes through the first back-pressure passage and exchanges heat with the heat storage element 4 before entering the gas storage element 50, thereby increasing the air pressure in the gas storage element 50. After the air pressure in the first high-pressure liquid storage tank is the same as the hydraulic pressure in the second high-pressure liquid storage tank, the eighth regulating valve 27 is closed.

[0078] The power generation process of the second power generation component is as follows: the first regulating valve 20 is opened to open the second gas transmission pipeline, and the eighth regulating valve 27 is opened to open a back pressure passage and the fourth regulating valve 23. The working fluid in the second high-pressure liquid storage tank enters the first turbine unit 13 under the set pressure to do work and then flows into the first high-pressure liquid storage tank, so that the operation of the first turbine unit 13 is stably maintained at the optimal working condition. If the working fluid is water, the operation of the first turbine unit 13 is stably maintained at the optimal working condition at a head of about 700m; as the liquid level in the first high-pressure liquid storage tank continues to increase, the air pressure inside it continues to increase on the basis of pre-pressure, and the compressed air in the first high-pressure liquid storage tank exchanges heat with the working fluid in the heat storage component 4 in the second heat exchanger 10 through the first back pressure passage, and the compressed air after heat exchange is passed into the gas storage component 50 to increase the gas pressure in the gas storage component 50, thereby maintaining the operation stability of the first turbine unit 13. Until all the working fluid enters the first high-pressure liquid storage tank, at which time the first high-pressure liquid storage tank is completely filled with compressed air, close the fourth regulating valve 23, and finally open the first pressure relief valve 18 to balance the air pressure inside the first high-pressure liquid storage tank, and then close the first pressure relief valve 18 and the eighth regulating valve 27.

[0079] The ninth regulating valve 29 is opened, and the compressed air in the second high-pressure liquid storage tank passes through the second back-pressure passage and exchanges heat with the heat storage element 4 before entering the gas storage element 50, thereby increasing the air pressure in the gas storage element 50. After the air pressure in the second high-pressure liquid storage tank is the same as the hydraulic pressure in the first high-pressure liquid storage tank, the ninth regulating valve 29 is closed.

[0080] In some embodiments, when the first water turbine unit 13 and the second water turbine unit 14 are maintained at the optimal working condition, their working water heads remain unchanged and can be expressed as:

[0081] H=H z +H p

[0082] The operating characteristic curve formula is:

[0083] η=f(P,H)

[0084] P=η t γQH=9.81η t QH

[0085]

[0086]

[0087] Where: η is the turbine efficiency; P is the output, kW; η t is the model efficiency; γ is the bulk density, kN / m 3 , 9.81 is the acceleration due to gravity, m / s 2 ; H is the head, m; Q is the flow, m 3 / s;n 11 It represents the rotation speed of a geometrically similar turbine when the runner diameter is 1m and the effective water head is 1m, m / s; Q 11 It represents the effective flow rate when the geometrically similar turbine has a runner diameter of 1m and an effective head of 1m, m 3 / s; n is the rotation speed, m / s; D 1 is the nominal diameter of the runner, m.

[0088] in Figure 4 is a diagram of the working range of the first turbine unit 13 and the second turbine unit 14, in which the ordinate n 11 It represents the rotation speed of a geometrically similar turbine when the runner diameter is 1m and the effective water head is 1m; the horizontal axis Q 11 It represents the effective flow rate when the geometrically similar turbine runner has a diameter of 1m and an effective head of 1m; Figure 5 is the relationship curve between the output of the first turbine unit 13 and the second turbine unit 14 and the water head. In the figure, the ordinate H represents the water head; the abscissa P represents the output; in the working water head range H min ~H maxTake eight water head values ​​H between i , and calculate the unit speed n corresponding to each water head 11i ;exist Figure 4 Each n 11i Draw a horizontal line with the model's certain efficiency line and intersect it at a series of points. m is converted to η, and P of each point is calculated at the same time. Each point is plotted in the P~H coordinate system and connected into a smooth curve.

[0089] In some embodiments, the power generation stage also includes, during the power generation process of the first power generation component, after all the working fluid enters the second high-pressure liquid storage component 3, closing the second back pressure passage and the first gas pipeline, opening the first back pressure passage, and utilizing the compressed air in the first high-pressure liquid storage component 2 to exchange heat with the heat storage component 4 through the first back pressure passage and then enter the gas storage component 50.

[0090] In some embodiments, the power generation stage also includes, during the power generation process of the second power generation component, after all the working fluid enters the first high-pressure liquid storage component 2, closing the first back pressure passage and the second gas pipeline, opening the second back pressure passage, and utilizing the compressed air in the second high-pressure liquid storage component 3 to exchange heat with the heat storage component 4 through the second back pressure passage and then enter the gas storage component 50.

[0091] Therefore, in the present application, a heat storage component 4 is used to compress the air, and during the power generation process of the bidirectional energy storage power generation system, the heat storage component 4 is used to realize the gas pressurization technology for the gas storage component 50, which can not only ensure the stable operation of the energy storage power generation system, but also place the bidirectional energy storage power generation system at any height, and has the advantages of low requirements for engineering geological conditions and high energy storage power generation efficiency; in addition, the first turbine unit 13 and the second turbine unit 14 arranged between the second high-pressure liquid storage tank and the first high-pressure liquid storage tank constitute a forward and reverse turbine unit, and bidirectional power generation is achieved through the change of air pressure inside the second high-pressure liquid storage tank and the first high-pressure liquid storage tank; and the first turbine unit 13 and the second turbine unit 14 are kept in the optimal efficiency range at all times by adjusting the internal pressure of the second high-pressure liquid storage tank and the first high-pressure liquid storage tank.

[0092] It should be noted that, in the description of this application, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In addition, in the description of this application, unless otherwise specified, the meaning of "plurality" is two or more.

[0093] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, segment or portion of code that includes one or more executable instructions for implementing the steps of a specific logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in the reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present application belong.

[0094] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0095] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A bidirectional energy storage and power generation system based on a compressed air unit, characterized in that: include A compressed air unit, comprising an air compression assembly and at least one air storage member; wherein the air storage member is connected to the air compression assembly, and the air storage member is used to store compressed air generated by the air compression assembly; A liquid heat storage unit, comprising a liquid storage component and a heat storage component which are interconnected, both containing a working fluid; wherein the heat storage component is respectively connected to the air compression component and the gas storage component for heat exchange, and stores the compression heat generated by the air compression component and provides heat to the gas storage component; A bidirectional energy storage power generation unit, comprising a first power generation component and a second power generation component; wherein the first power generation component and the second power generation component are respectively connected to the liquid storage component and the air storage component, and the working fluid in the first power generation component and the second power generation component circulate with each other, wherein the input compressed air drives the stored working fluid to flow toward each other to realize bidirectional power generation and work; The first power generation assembly comprises a first high-pressure liquid storage assembly and a second turbine assembly; wherein the liquid inlet of the first high-pressure liquid storage assembly is connected to the liquid storage member, and its air inlet is communicated with the air storage member through a first air pipeline, and the liquid outlet of the first high-pressure liquid storage assembly is communicated with the liquid inlet of the second turbine assembly; the liquid outlet of the second turbine assembly is connected to the second power generation assembly; the second power generation assembly comprises a second high-pressure liquid storage assembly and a first turbine assembly; wherein the liquid inlet of the second high-pressure liquid storage assembly is connected to the liquid outlet of the second turbine assembly, and its air inlet is communicated with the air storage member through a second air pipeline, and the second high-pressure liquid storage assembly The liquid outlet of the component is respectively communicated with the liquid inlet of the first turbine unit and the liquid storage component; the liquid outlet of the first turbine unit is connected to the liquid inlet of the second high-pressure liquid storage component; the sixth regulating valve, the fifth regulating valve and the second regulating valve are respectively arranged on the first gas transmission pipeline, between the liquid outlet of the second turbine unit and the second power generation component, and between the liquid inlet of the first high-pressure liquid storage component and the liquid storage component; the first regulating valve, the fourth regulating valve and the third regulating valve are respectively arranged on the second gas transmission pipeline, between the liquid outlet of the first turbine unit and the first high-pressure liquid storage component, and between the second high-pressure liquid storage component and the liquid storage component; and a back-pressure passage, the back-pressure passage comprising a first back-pressure passage connecting the first power generation component and the heat storage component and a second back-pressure passage connecting the second power generation component and the heat storage component; the first back-pressure passage and the second back-pressure passage are used to respectively recover the compressed air in the first power generation component and the second power generation component and pass them into the air storage component after heat exchange with the heat storage component.

2. The power generation system according to claim 1, characterized in that: The first power generation assembly also includes a first water-gas separator, a first pressure stabilizer and a first pressure relief valve which are sequentially arranged on the first gas transmission pipeline according to the gas transmission direction.

3. The power generation system according to claim 2, characterized in that: The first pressure relief valve is provided with a pressure sensor.

4. The power generation system according to any one of claims 1 to 3, characterized in that: A first pressure regulating well is arranged between the second regulating valve and the first high-pressure liquid storage assembly.

5. The power generation system according to claim 4, characterized in that: The second power generation assembly also includes a second water-gas separator, a second pressure stabilizer and a second pressure relief valve which are sequentially arranged on the second gas transmission pipeline according to the gas transmission direction.

6. The power generation system according to claim 5, characterized in that: The second pressure relief valve is provided with a pressure sensor.

7. The power generation system according to claim 4, characterized in that: A second pressure regulating well is arranged between the third regulating valve and the second high-pressure liquid storage assembly.

8. A bidirectional energy storage and power generation method based on a compressed air unit, characterized in that: The power generation system according to any one of claims 1 to 7 is used to generate electricity.

9. The method according to claim 8, characterized in that The process includes: Energy storage stage: the air compression component compresses the input air and stores the generated compressed air in the air storage component after exchanging heat with the working fluid liquid in the heat storage component; Power generation stage: including the power generation process of the first power generation component and the power generation process of the second power generation component; The power generation process of the first power generation assembly: in the initial stage, the first high-pressure liquid storage assembly is filled with working fluid, and the second high-pressure liquid storage assembly is empty; the second gas pipeline is opened to pre-pressurize the second high-pressure liquid storage assembly until the pressure of the second high-pressure liquid storage assembly is balanced with that of the first high-pressure liquid storage assembly, and then the second gas pipeline is closed; The second regulating valve and the third regulating valve are closed, and the first gas transmission pipeline, the second back pressure passage and the fifth regulating valve are opened. The working fluid in the first high-pressure liquid storage assembly enters the second turbine unit under the set pressure to perform work and then flows into the second high-pressure liquid storage assembly, so that the operation of the second turbine unit is stably maintained at the optimal working condition; at the same time, the compressed air in the second high-pressure liquid storage assembly is passed into the gas storage component for heat increase and pressure compensation after heat exchange with the heat storage component through the second back pressure passage; the fifth regulating valve is closed until all the working fluid enters the second high-pressure liquid storage assembly, and the air pressure in the second high-pressure liquid storage assembly is balanced; The power generation process of the second power generation component: the second regulating valve and the third regulating valve are closed, and the second gas transmission pipeline, the first back pressure passage and the fourth regulating valve are opened, so that the working fluid in the second high-pressure liquid storage component enters the first turbine unit under the set pressure to perform work and then flows into the first high-pressure liquid storage component, so that the operation of the first turbine unit is stably maintained at the optimal working condition; at the same time, the compressed air in the first high-pressure liquid storage component is passed into the gas storage component after heat exchange and temperature increase with the heat storage component through the first back pressure passage; The air pressure in the first high-pressure liquid storage component is balanced until all the working fluid enters the first high-pressure liquid storage component.

10. The method according to claim 9, characterized in that The power generation stage also includes, during the power generation process of the first power generation component, after all the working fluid enters the second high-pressure liquid storage component, closing the second back-pressure passage and the first gas pipeline, opening the first back-pressure passage, and using the compressed air in the first high-pressure liquid storage component to exchange heat with the heat storage component through the first back-pressure passage and then pass into the gas storage component until the air pressure in the first high-pressure liquid storage component is the same as the hydraulic pressure in the second high-pressure liquid storage component.

11. The method according to claim 9, characterized in that The power generation stage also includes, during the power generation process of the second power generation component, after all the working fluid enters the first high-pressure liquid storage component, closing the first back-pressure passage and the second gas pipeline, opening the second back-pressure passage, and using the compressed air in the second high-pressure liquid storage component to exchange heat with the heat storage component through the second back-pressure passage and then pass into the gas storage component until the air pressure in the second high-pressure liquid storage component is the same as the hydraulic pressure in the first high-pressure liquid storage component.

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