High-voltage energy storage power generation system

Abstract

The present invention relates to a high-voltage energy storage power generation system. The high-voltage energy storage power generation system includes a first liquid storage tank, a second liquid storage tank, a high-voltage energy storage tank, a piston cylinder, a hydraulic drive mechanism, and a power generation device. The piston cylinder includes a cylinder body and a piston member slidably mounted in the cylinder body. A first inlet and a first outlet are provided at one end of the cylinder body, and a second inlet and a second outlet are provided at the other end. The first inlet is connected to the first liquid storage tank via a first liquid inlet valve and a first liquid pump in sequence. The first outlet is connected to the high-voltage energy storage tank via a first liquid outlet valve. The second inlet is connected to the liquid inlet of the hydraulic drive mechanism and the outlet of the second liquid pump respectively via a second liquid inlet valve. The inlet of the second liquid pump is connected to the second liquid storage tank. The second outlet is connected to the liquid outlet of the hydraulic drive mechanism and the second liquid storage tank respectively via a second liquid outlet valve. The above-mentioned high-voltage energy storage power generation system has the advantages of high energy conversion efficiency and low energy loss during energy storage, constant frequency power generation during power generation, and is conducive to grid connection.

Description

Technical Field

[0001] The present invention relates to the technical field of liquid air energy storage, and in particular to a high-voltage energy storage power generation system. Background Art

[0002] Currently, compressed air energy storage is one of the primary methods for achieving high-power energy storage. Compressed air energy storage technology compresses air and stores it in sealed, high-pressure containers or natural geological caverns, generating compressed air potential energy. When energy is needed, the compressed air is released through an expander, which then generates power to drive a generator. Currently, conventional air compressors are typically used to compress air. However, because the compression ratio of a single compressor is limited, a multi-stage compression system is required for high-pressure compressed air, resulting in complex and inefficient systems. Summary of the Invention

[0003] In response to the above-mentioned deficiencies in the prior art, this application proposes a high-voltage energy storage power generation system.

[0004] A high-pressure energy storage power generation system comprises a first liquid storage tank, a second liquid storage tank, a high-pressure energy storage tank, a piston cylinder, a hydraulic drive mechanism and a power generation device connected to the hydraulic drive mechanism;

[0005] The piston cylinder includes a hollow cylinder body and a piston member slidably mounted in the cylinder body; the piston member divides the space in the cylinder body into a first chamber and a second chamber; a first inlet and a first outlet communicating with the first chamber are formed at one end of the cylinder body, and a second inlet and a second outlet communicating with the second chamber are formed at the other end;

[0006] The first inlet is connected to the first liquid storage tank through the first liquid inlet valve and the first liquid pump in sequence; the first outlet is connected to the high-pressure accumulator tank through the first liquid outlet valve; the second inlet is connected to the liquid inlet of the hydraulic drive mechanism and the outlet of the second liquid pump respectively through the second liquid inlet valve; the inlet of the second liquid pump is connected to the second liquid storage tank; the second outlet is connected to the second liquid storage tank through the second liquid outlet valve; and the liquid outlet of the hydraulic drive mechanism is connected to the second liquid storage tank.

[0007] The energy storage and power generation system controls the opening and closing sequence of the first liquid inlet valve, the first liquid outlet valve, the second liquid inlet valve, and the second liquid outlet valve, and coordinates the operation of the first and second liquid valves to gradually transfer the first liquid from the first liquid storage tank to the high-pressure accumulator tank, thereby compressing the gas within the high-pressure accumulator tank until the gas pressure within the high-pressure accumulator tank reaches a preset value, thus completing the entire energy storage process. During the process of compressing the gas within the high-pressure accumulator tank via the first liquid, the gas within the high-pressure accumulator tank is compressed by the liquid, resulting in high energy conversion efficiency.

[0008] In one embodiment, there are multiple piston cylinders; each first inlet is connected to the outlet of the first liquid pump through the first liquid inlet valve; the inlet of the first liquid pump is connected to the first liquid storage tank; each first outlet is connected to the high-pressure accumulator tank through the first liquid outlet valve; each second inlet is connected to the liquid inlet of the hydraulic drive mechanism and the outlet of the second liquid pump respectively through the second liquid inlet valve; each second outlet is connected to the second liquid storage tank through the second liquid outlet valve;

[0009] The high-voltage energy storage power generation system also includes a control device; the control device is used to control the opening and closing of multiple first liquid inlet valves, multiple first liquid outlet valves, multiple second liquid inlet valves and multiple second liquid outlet valves according to preset instructions, so that the sliding direction of some of the piston members is opposite to the sliding direction of the remaining piston members.

[0010] In one embodiment, the system further includes a first low-pressure pipeline, a first high-pressure pipeline, a second low-pressure pipeline, and a second high-pressure pipeline;

[0011] The first low-pressure pipeline includes a first low-pressure main pipe and a plurality of first low-pressure branch pipes; one end of the first low-pressure main pipe is connected to the first liquid storage tank, and the other end is connected to each of the plurality of first low-pressure branch pipes; one end of each of the plurality of first low-pressure branch pipes, which is remote from the first low-pressure main pipe, is connected to each of the plurality of first inlets in a one-to-one correspondence; the first liquid pump is disposed on the first low-pressure main pipe; and each of the first low-pressure branch pipes is provided with a first liquid inlet valve;

[0012] The first high-pressure pipeline includes a first high-pressure main pipe and a plurality of first high-pressure branch pipes; one end of the first high-pressure main pipe is connected to the high-pressure accumulator tank, and the other end is connected to each of the plurality of first high-pressure branch pipes; ends of the plurality of first high-pressure branch pipes remote from the first high-pressure main pipe are connected to each of the plurality of first outlets in a one-to-one correspondence; each of the first high-pressure branch pipes is provided with a first liquid outlet valve;

[0013] The second low-pressure pipeline includes a second low-pressure main pipe and a plurality of second low-pressure branch pipes; the two ends of the second low-pressure main pipe are respectively connected to the liquid outlet of the hydraulic drive mechanism and the second liquid storage tank; one end of each of the second low-pressure branch pipes is respectively connected to the plurality of second outlets in a one-to-one correspondence, and the other end is all connected to the second low-pressure main pipe; each of the second low-pressure branch pipes is provided with a second liquid outlet valve; and a back-pressure valve is provided at one end of the second low-pressure main pipe close to the second liquid storage tank.

[0014] The second high-pressure pipeline includes a second high-pressure main pipe and multiple second high-pressure branch pipes; the two ends of the second high-pressure main pipe are respectively connected to the liquid inlet of the hydraulic drive mechanism and the second liquid storage tank; one end of the multiple second high-pressure branch pipes is respectively connected to the multiple second inlets one by one, and the other ends are all connected to the second high-pressure main pipe; each of the second high-pressure branch pipes is provided with the second liquid inlet valve; the second liquid pump and the one-way valve are provided at the end of the second high-pressure main pipe close to the second liquid storage tank.

[0015] This makes it easier to connect the various parts of the high-voltage energy storage power generation system.

[0016] The above-mentioned high-voltage energy storage power generation system has an operating mode including energy storage mode and power generation mode;

[0017] When in the energy storage mode, by controlling the opening and closing sequence of the first liquid inlet valve, the first liquid outlet valve, the second liquid inlet valve and the second liquid outlet valve, the first liquid in the first liquid storage tank is firstly injected into the first chamber by the first liquid pump, and then the second liquid is injected into the second chamber by the second liquid pump, so as to push the piston to transfer the first liquid previously injected into the cylinder to the high-pressure accumulator tank to compress the gas in the high-pressure accumulator tank. In this way, through the reciprocating operation of the piston, more first liquid is gradually transferred from the first liquid storage tank to the high-pressure accumulator tank until the gas pressure in the high-pressure accumulator tank is compressed to a preset value, and the entire energy storage process is completed;

[0018] When in the power generation mode, by controlling the first liquid inlet valve and the second liquid outlet valve corresponding to one or more piston cylinders to close, and the first liquid outlet valve and the second liquid inlet valve to open, the gas in the high-pressure accumulator tank expands, pushing the first liquid in the high-pressure accumulator tank into the first chamber corresponding to the one or more piston cylinders, so as to push the piston member to push the second liquid in the second chamber corresponding to the one or more piston cylinders into the hydraulic drive mechanism, so that the hydraulic drive mechanism operates to drive the power generation device to generate electricity; at the same time, by controlling the opening of the second liquid outlet valve and the first liquid inlet valve corresponding to the remaining one or more piston cylinders, and closing the first liquid outlet valve and the second liquid inlet valve, the second liquid at the liquid outlet of the hydraulic drive mechanism flows back to the second chamber corresponding to the remaining one or more piston cylinders, so as to push the piston member to push the first liquid in the first chamber into the first liquid storage tank, until the compressed air energy in the high-pressure accumulator tank is released, and the entire power generation process is completed.

[0019] In this way, the operating modes of the above-mentioned high-voltage energy storage and power generation system include energy storage mode and power generation mode. The control device controls the opening and closing of multiple first liquid inlet valves, multiple first liquid outlet valves, multiple second liquid inlet valves and multiple second liquid outlet valves in a certain sequence, and cooperates with the operation of the first liquid pump and the second liquid pump. In the energy storage mode, the first liquid can be continuously delivered to the high-pressure energy storage tank, and in the power generation mode, the second liquid can be continuously delivered to the hydraulic drive mechanism, and the first liquid can be returned to the first liquid storage tank.

[0020] In one embodiment, the invention further includes a heat insulator, which is laterally and slidably disposed within the high-pressure accumulator tank and is used to separate the gas and liquid within the high-pressure accumulator tank. The heat insulator is used to separate the liquid and gas within the high-pressure accumulator tank to prevent heat generated during gas compression from being transferred to the liquid within the high-pressure accumulator tank.

[0021] In one embodiment, a heat insulating layer is formed on the outer surface of the high-pressure accumulator tank. The provision of the heat insulating layer can improve the heat insulating performance of the high-pressure accumulator tank.

[0022] In one embodiment, the top of the high-pressure energy storage tank is provided with an air inlet and outlet hole; the high-pressure energy storage power generation system further includes an air pipeline connected to the air inlet and outlet hole; and the air pipeline is provided with an air valve. This allows for functions such as air injection and ventilation into the high-pressure energy storage tank.

[0023] In one embodiment, the first liquid pump is a water pump; the second liquid pump is an oil pump; the hydraulic drive mechanism is a hydraulic motor; and the power generation device includes a gearbox connected to the hydraulic motor and a generator connected to the gearbox.

[0024] In one embodiment, the hydraulic motor is a variable speed motor; the high-voltage energy storage power generation system further includes a controller and a speed sensor; the speed sensor is communicatively connected to the controller and is used to obtain the output speed of the variable speed motor in real time; the controller is electrically connected to the variable speed motor and is used to adaptively adjust the displacement of the hydraulic motor based on the output speed, thereby ensuring a constant speed output of the variable speed motor. This ensures that even if the input flow of the variable speed motor fluctuates, the variable speed motor can maintain a constant speed output, maintaining constant frequency power generation of the generator and facilitating grid connection.

[0025] In one embodiment, the side wall of the first liquid storage tank is separated into a first opening and a second opening. The first opening is connected to the first inlet and is provided with the first liquid pump in the communication passage. The second opening is connected to the first inlet and is provided with a liquid return valve in the communication passage. In this way, the liquid return passage and liquid outlet passage of the first liquid storage tank are independently provided to facilitate the return of the first liquid.

[0026] In this application, because the gas in the high-pressure accumulator is compressed by liquid, energy conversion efficiency is high. The high-pressure accumulator, with its thermal insulation layer and intermediate insulator, ensures that the heat energy generated by compression is not lost. Under certain conditions, this heat energy can be converted into gas potential energy for utilization. Furthermore, the hydraulic drive mechanism achieves constant output speed, maintaining constant frequency power generation for the generator, facilitating grid connection. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a simplified structural diagram of a high-voltage energy storage power generation system in a preferred embodiment of the present invention.

[0028] Explanation of the reference numerals in the specific embodiment: 10, high-voltage energy storage power generation system; 100, first liquid storage tank; 110, first opening; 120, second opening; 200, second liquid storage tank; 300, high-voltage energy storage tank; 400, piston cylinder; 410, cylinder body; 411, first chamber; 412, second chamber; 420, piston member; 430, first liquid inlet valve; 440, first liquid outlet valve; 450, second liquid inlet valve; 460, second liquid outlet valve; 500, hydraulic drive mechanism; 600, power generation device; 610, gearbox; 62 0. Generator; 710. First liquid pump; 720. Second liquid pump; 810. First low-pressure pipeline; 811. First low-pressure main pipe; 812. First low-pressure branch pipe; 820. First high-pressure pipeline; 821. First high-pressure main pipe; 822. First high-pressure branch pipe; 830. Second low-pressure pipeline; 831. Second low-pressure main pipe; 832. Second low-pressure branch pipe; 840. Second high-pressure pipeline; 841. Second high-pressure main pipe; 842. Second high-pressure branch pipe; 910. One-way valve; 920. Back-pressure valve; 930. Liquid return valve; 20. Power grid. DETAILED DESCRIPTION

[0029] To facilitate understanding of the present invention, the present invention will be described more fully below with reference to the accompanying drawings. Preferred embodiments of the present invention are shown in the accompanying drawings. However, the present invention may be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and comprehensive understanding of the present disclosure.

[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this invention pertains. The terms used in this specification of the present invention are for the purpose of describing specific embodiments only and are not intended to limit the present invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0031] When describing positional relationships, unless otherwise specified, when an element is referred to as being "on" another element, it can be directly on the other element or intervening elements may also exist. It is also understood that when an element is referred to as being "between" two elements, it can be the only one between the two elements, or one or more intervening elements may also exist.

[0032] In the case of using “including,” “having,” and “comprising” described herein, another component may be added unless a clear limiting term such as “only,” “consisting of,” etc. is used. Unless mentioned otherwise, a term in the singular form may include a plural form and should not be understood as having one number.

[0033] In addition, the drawings are not drawn to a 1:1 scale, and the relative sizes of the elements in the drawings are drawn only as examples and not necessarily according to the true scale.

[0034] Figure 1 The structure of a high-voltage energy storage power generation system in one embodiment of the present invention is shown. For ease of explanation, the accompanying drawings only show structures related to the embodiment of the present invention.

[0035] See also Figure 1 The high-pressure energy storage power generation system 10 in a preferred embodiment of the present invention includes a first liquid storage tank 100, a second liquid storage tank 200, a high-pressure energy storage tank 300, a piston cylinder 400, a hydraulic drive mechanism 500 and a power generation device 600.

[0036] The first liquid storage tank 100 is used to store a first liquid. The second liquid storage tank 200 is used to store a second liquid. The first liquid and the second liquid can be the same liquid or different liquids. The space within the high-pressure accumulator tank 300 is used to store and compress gas. Specifically, the first liquid is insoluble in or has very low solubility in the gas within the high-pressure accumulator tank 300. The shapes of the first and second liquid storage tanks 100, 200 are not limited, as long as they can store liquids. The shape of the high-pressure accumulator tank 300 is also not limited, as long as it can withstand high pressure, high temperature, and good sealing properties.

[0037] The piston cylinder 400 includes a cylinder body 410 with a hollow structure and a piston member 420 slidably mounted in the cylinder body 410. The piston member 420 divides the space in the cylinder body 410 into an independent first chamber 411 and a second chamber 412. One end of the cylinder body 411 is provided with a first inlet (not marked in the figure) and a first outlet (not marked in the figure) connected to the first chamber 411, and the other end is provided with a second inlet (not marked in the figure) and a second outlet (not marked in the figure) connected to the second chamber 412. The cylinder body 411 can be arranged vertically or horizontally. Specifically, in the present embodiment, the cylinder body 411 is arranged horizontally. When the cylinder body 411 is arranged horizontally, the first chamber 411 and the second chamber 412 are arranged at intervals in the horizontal direction.

[0038] The first inlet is connected to the first liquid storage tank 100 via the first inlet valve 430 and the first liquid pump 710. The first outlet is connected to the high-pressure accumulator tank 300 via the first outlet valve 440. The second inlet is connected to the inlet of the hydraulic drive mechanism 500 and the outlet of the second liquid pump 720 via the second inlet valve 450. The inlet of the second liquid pump 720 is connected to the second liquid storage tank 200. The second outlet is connected to the outlet of the hydraulic drive mechanism 500 and the second liquid storage tank 200 via the second outlet valve 460.

[0039] For ease of understanding, the working process of the high-voltage energy storage power generation system 10 is briefly described below:

[0040] First, the first liquid inlet valve 430 and the second liquid outlet valve 460 are opened, the first liquid outlet valve 440 and the second liquid inlet valve 450 are closed, and the first liquid pump 710 is started to suck the first liquid in the first liquid storage tank 100 into the first chamber 411, so as to push the piston 420 to slide in the direction toward the second inlet. At the same time, the second liquid in the second chamber 412 flows back into the second liquid storage tank 200 through the second outlet. When the piston 412 slides to the end of the cylinder body 411 provided with the first inlet, the first liquid inlet valve 430 and the second liquid outlet valve 460 are closed, the first liquid outlet valve 440 and the second liquid inlet valve 450 are opened, and the second liquid pump 720 is started. The second liquid in the second liquid storage tank 200 is injected into the second chamber 412, and the second liquid is used to push the piston member 412 to slide in the direction toward the first inlet, pushing the first liquid in the first chamber 411 into the high-pressure energy storage tank 300, thereby using the first liquid to compress the gas in the high-pressure energy storage tank 300. This process is repeated to gradually transfer more first liquid from the first liquid storage tank 100 to the high-pressure energy storage tank 300, and continuously compress the gas in the high-pressure energy storage tank 300 until the gas pressure in the high-pressure energy storage tank 300 is compressed to a preset value, thereby converting electrical energy into potential energy and thermal energy of the compressed gas for storage.

[0041] It should be noted that during the energy storage process, the hydraulic drive mechanism 500 and the power generation device 600 are not in operation. In order to more intuitively understand the energy storage process of the high-voltage energy storage power generation system 10, when the first liquid enters the high-voltage energy storage tank 300 and compresses the gas in the high-voltage energy storage tank 300, the state between the gas and the liquid in the high-voltage energy storage tank 300 is as follows: Figure 1 As shown, Q represents the gas in the high-pressure accumulator tank 300 , and L represents the liquid in the high-pressure accumulator tank 300 .

[0042] Therefore, by cooperating with the first liquid pump 710 and the second liquid pump 720 respectively, the first liquid can compress the gas in the high-pressure accumulator tank 300, thereby realizing energy conversion and storage. In addition, in the process of compressing the gas in the high-pressure accumulator tank 300 by the first liquid, the gas in the high-pressure accumulator tank 300 is compressed by the liquid, and the energy conversion efficiency is high.

[0043] In some embodiments, there are multiple piston cylinders 400. Each first inlet is connected to the outlet of the first liquid pump 710 via a first inlet valve 430. The inlet of the first liquid pump 710 is connected to the first liquid storage tank 100. Each first outlet is connected to the high-pressure accumulator tank 300 via a first outlet valve 440. Each second inlet is connected to the inlet of the hydraulic drive mechanism 500 and the outlet of the second liquid pump 720, respectively, via a second inlet valve 450. Each second outlet is connected to the second liquid storage tank 200 and the outlet of the hydraulic drive mechanism 500, respectively, via a second outlet valve 460.

[0044] The high-voltage energy storage power generation system 10 further includes a control device (not shown). The control device is configured to control the opening and closing of the plurality of first liquid inlet valves 430, the plurality of first liquid outlet valves 440, the plurality of second liquid inlet valves 450, and the plurality of second liquid outlet valves 460 according to preset instructions, so that the sliding direction of some piston members 420 is opposite to the sliding direction of the remaining piston members 420.

[0045] It should be noted that the term "plurality" refers to a number greater than or equal to 2. The operating modes of the high-voltage energy storage and power generation system 10 include an energy storage mode and a power generation mode.

[0046] For the convenience of explanation, the working process of the above-mentioned high-voltage energy storage power generation system 10 is briefly described below using two piston cylinders 400 as an example, and the first liquid inlet valve 430 connected to one piston cylinder 400, the first liquid outlet valve 440 connected to the other piston cylinder 400, the second liquid outlet valve 460 connected to one piston cylinder 400, and the second liquid inlet valve 450 connected to one piston cylinder 400 are divided into one group, and the first liquid outlet valve 440 connected to one piston cylinder 400, the first liquid inlet valve 430 connected to the other piston cylinder 400, the second liquid inlet valve 450 connected to one piston cylinder 400, and the second liquid outlet valve 460 connected to the other piston cylinder 400 are divided into another group:

[0047] When in energy storage mode: the first liquid pump 710 and the second liquid pump 720 are in continuous operation, and the control device is used to control the two groups of valves to open and close alternately (that is, when all valves in one group of valves are open, all valves in the other group of valves are closed), so that the two piston members 420 can slide in opposite or opposite directions in their respective cylinder bodies 410, so that one piston cylinder 400 is working to inject the first liquid in the first liquid storage tank 100 into the first chamber 411, while the other piston cylinder 400 is working to inject the first liquid in the first chamber 411 into the high-pressure accumulator tank 300. This alternating reciprocating operation can continuously inject the first liquid into the high-pressure accumulator tank 300 to continuously compress the gas in the high-pressure accumulator tank 300 until the pressure of the compressed gas in the high-pressure accumulator tank 300 reaches a preset pressure value, and the entire energy storage operation is completed;

[0048] When in power generation mode: the hydraulic drive mechanism 500 is started, and the control device is used to control the two sets of valves to open and close alternately, so that the two piston members 420 can slide in opposite or opposite directions in their respective cylinder bodies 410, so that one piston cylinder 400 pushes the second liquid in its own second chamber 412 to the hydraulic drive mechanism 500 to drive the hydraulic drive mechanism 500 to operate. At the same time, the other piston cylinder 400 uses the second liquid refluxed from the hydraulic drive mechanism 500 to push the first liquid in the first chamber 411 into the first liquid storage tank 100. This alternating reciprocating process is carried out until the liquid in the high-pressure accumulator tank 300 is drained. The hydraulic drive mechanism 500 can then be continuously supplied with liquid uninterruptedly, ensuring that the power generation device 600 can output electrical energy stably and continuously.

[0049] In order to provide a more comprehensive description of the above-mentioned high-voltage energy storage and power generation system 10, a brief description is also given of the situation when the number of piston cylinders 400 is greater than 2: during use, the control device controls the multiple first liquid inlet valves 430, the multiple first liquid outlet valves 440, the multiple second liquid inlet valves 450 and the multiple second liquid outlet valves 460 to open and close in a certain sequence, so that the multiple piston members 420 slide in sequence, and ensure that the sliding direction of each piston member 420 is opposite to or opposite to the sliding direction of at least one other piston member 420, so that the first liquid is injected into the first chamber 411 and the first liquid in the first chamber 411 is pushed into the high-voltage energy storage tank 300 during the energy storage process. The continuity is also improved, and the second liquid in the second chamber 412 is transported to the hydraulic drive mechanism 500 and the first liquid in the first chamber 411 is returned to the first liquid storage tank 100 during the power generation process. In this way, the above-mentioned high-voltage energy storage and power generation system 10 can be ensured to operate smoothly and continuously.

[0050] It should be noted that during the power generation process, both the first liquid pump 710 and the second liquid pump 720 are not in operation.

[0051] For ease of understanding, the usage scenarios of the above-mentioned high-voltage energy storage power generation system 10 are illustrated as follows: in the above-mentioned high-voltage energy storage power generation system 10, the electric energy of the municipal power grid 20 can be used to drive the first liquid pump 710 and the second liquid pump 720 to work to realize energy storage; when the above-mentioned high-voltage energy storage power generation system 10 is generating electricity, the electric energy generated by the power generation device 600 can be directly input into the national power grid 20, or directly supply power to electrical equipment.

[0052] Furthermore, in some embodiments, the high-voltage energy storage power generation system 10 further includes a first low-pressure pipeline 810 , a first high-pressure pipeline 820 , a second low-pressure pipeline 830 and a second high-pressure pipeline 840 .

[0053] The first low-pressure pipeline 810 includes a first low-pressure main pipe 811 and multiple first low-pressure branch pipes 812. One end of the first low-pressure main pipe 811 is connected to the first liquid storage tank 100, and the other end is connected to each of the multiple first low-pressure branch pipes 812. The ends of the multiple first low-pressure branch pipes 812, remote from the first low-pressure main pipe 811, are connected to a plurality of first inlets in a one-to-one correspondence. The first liquid pump 710 is mounted on the first low-pressure main pipe 811. Each first low-pressure branch pipe 812 is equipped with a first liquid inlet valve 430.

[0054] The first high-pressure pipeline 820 includes a first high-pressure main pipe 821 and multiple first high-pressure branch pipes 822. One end of the first high-pressure main pipe 821 is connected to the high-pressure accumulator tank 300, and the other end is connected to each of the multiple first high-pressure branch pipes 822. The ends of the multiple first high-pressure branch pipes 822, remote from the first high-pressure main pipe 821, are connected to a plurality of first outlets in a one-to-one correspondence. Each first high-pressure branch pipe 822 is provided with a first liquid outlet valve 440.

[0055] The second low-pressure pipeline 830 includes a second low-pressure main pipe 831 and multiple second low-pressure branch pipes 832. The two ends of the second low-pressure main pipe 831 are connected to the liquid outlet of the hydraulic drive mechanism 500 and the second liquid storage tank 200, respectively. One end of each of the multiple second low-pressure branch pipes 832 is connected to a corresponding plurality of second outlets, and the other end is connected to the second high-pressure branch pipe 832. Each second low-pressure branch pipe 832 is provided with a second liquid outlet valve 460. A backpressure valve 920 is provided at the end of the second low-pressure main pipe 831 near the second liquid storage tank 200.

[0056] The second high-pressure pipeline 840 includes a second high-pressure main pipe 841 and multiple second high-pressure branch pipes 842. The two ends of the second high-pressure main pipe 841 are connected to the liquid inlet of the hydraulic drive mechanism 500 and the second liquid storage tank 200, respectively. One end of each of the multiple second high-pressure branch pipes 842 is connected to a plurality of second inlets in a one-to-one correspondence, and the other end of each second high-pressure branch pipe 842 is connected to the second high-pressure main pipe 841. Each second high-pressure branch pipe 842 is provided with a second liquid inlet valve 450. The second liquid pump 720 and a one-way valve 910 are provided at the end of the second high-pressure main pipe 841 near the second liquid storage tank 200.

[0057] In this way, the various components of the high-voltage energy storage power generation system 10 can be connected through the first high-pressure pipeline 820 , the second high-pressure pipeline 840 , the first low-pressure pipeline 810 and the second low-pressure pipeline 830 .

[0058] Among them, the setting of the one-way valve 910 can prevent the second liquid in the second high-pressure pipe from flowing back into the second liquid storage tank 200, so as to ensure that during the power generation process of the above-mentioned high-pressure energy storage power generation system 10, the second liquid in the second chamber 412 and the fourth chamber 4212 can only flow to the hydraulic drive mechanism 500.

[0059] The back pressure valve 920 can set different back pressures in the second low-pressure main pipe 831. For example, during the energy storage process, the back pressure of the back pressure valve 920 can be adjusted to the minimum to ensure that the second liquid in each second chamber 412 can flow back smoothly into the second liquid storage tank 200; during the power generation process, the back pressure of the back pressure valve 920 is adjusted to a preset pressure value to ensure that the second liquid at the liquid outlet of the hydraulic drive mechanism 500 can flow directly back into the second chamber 412, thereby avoiding the second liquid at the liquid outlet of the hydraulic drive mechanism 500 from flowing back into the second liquid storage tank 200, thereby improving the power generation reliability.

[0060] Of course, in other embodiments, the first high-pressure pipeline 820, the first low-pressure pipeline 810, the second high-pressure pipeline 840 and the second low-pressure pipeline 830 can be replaced by other forms of passages. For example, when the high-pressure energy storage power generation system 10 is designed to be very small, and the rest of the parts except the hydraulic drive mechanism 500 and the power generation device 600 are an integral structure, then the communication channels between the various parts can be directly formed inside this whole.

[0061] In some embodiments, the high-voltage energy storage power generation system 10 further includes a heat insulator (not shown). The heat insulator is laterally and slidably disposed in the high-voltage energy storage tank 300 to separate the gas and liquid in the high-voltage energy storage tank 300.

[0062] The thermal insulator can be a rigid part with thermal insulation properties, or a flexible part with thermal insulation properties, as long as it can separate the liquid and gas in the high-pressure accumulator tank 300 to prevent the heat generated during the gas compression process from being transferred to the liquid in the high-pressure accumulator tank 300, thereby reducing the energy loss caused by the heat energy in the gas being transferred to the first liquid.

[0063] It should be noted that when there is liquid in the high-pressure energy storage tank 300, the insulator is located on the liquid surface and moves up and down in the high-pressure energy storage tube as the liquid surface rises and falls; when there is no liquid in the high-pressure energy storage tank 300, the insulator is located at the bottom of the high-pressure energy storage tank 300 and covers the liquid inlet in the high-pressure energy storage tank 300.

[0064] In some embodiments, a thermal insulation layer (not shown) is formed on the outer surface of the high-pressure accumulator tank 300. The thermal insulation layer can be a thermal insulation member wrapped around the outer surface of the high-pressure accumulator tank 300, a thermal insulation coating applied to one side of the outer surface of the high-pressure accumulator tank 300, or a thermal insulation structure formed on the outer surface of the high-pressure accumulator tank 300 by other means. The provision of the thermal insulation layer prevents heat generated during the compression process of the gas within the high-pressure accumulator tank 300 from being lost to the outside world, ensuring that heat energy is not lost. Under certain conditions, this heat energy can be converted into potential energy of the gas for utilization.

[0065] In some embodiments, the top of the high-pressure accumulator tank 300 is provided with an air inlet and outlet (not shown). The high-pressure energy storage power generation system 10 also includes an air pipeline connected to the air inlet and outlet. The air pipeline is provided with an air valve. Thus, the air pipeline and the air valve can be used to perform functions such as air injection and ventilation in the high-pressure accumulator tank 300.

[0066] In some embodiments, the first liquid pump 710 is a water pump. The second liquid pump 720 is an oil pump. The hydraulic drive mechanism 500 is a hydraulic motor. The power generation device 600 includes a gearbox 610 drivingly connected to the hydraulic motor and a generator 620 drivingly connected to the gearbox 1001.

[0067] In other embodiments of the present invention, the first liquid and the second liquid may also be water or hydraulic oil at the same time, or may be other liquids besides water and hydraulic oil, as long as the second liquid can drive the hydraulic drive mechanism 500 to operate, and the first liquid is insoluble in or has extremely low solubility in the gas in the high-pressure energy storage tank 300.

[0068] Furthermore, in some embodiments, the hydraulic motor is a variable displacement motor. The high-voltage energy storage power generation system 10 also includes a controller (not shown) and a speed sensor (not shown). The speed sensor is communicatively connected to the controller and is used to obtain the output speed of the variable displacement motor in real time. The controller is electrically connected to the variable displacement motor and is used to adaptively adjust the displacement of the variable displacement motor based on the output speed, so that the variable displacement motor outputs a constant speed.

[0069] The controller may be a control mechanism provided on the variable motor, or may be the control device used in the aforementioned embodiment to control the opening and closing of the first liquid inlet valve 430, the first liquid outlet valve 440, the second liquid inlet valve 450, and the second liquid outlet valve 460. Specifically, the speed sensor is provided on the variable motor to obtain the actual output speed of the variable motor in real time.

[0070] Specifically, when the actual output speed measured by the speed sensor exceeds a preset threshold, the controller immediately increases the displacement of the variable motor until the motor's output speed reaches the preset threshold. When the actual output speed measured by the speed sensor falls below the preset threshold, the controller immediately decreases the displacement of the variable motor until the motor's output speed reaches the preset threshold. This ensures constant output speed even when the input flow rate fluctuates, maintaining constant frequency power generation and facilitating grid connection.

[0071] In some embodiments, a first opening 110 and a second opening 120 are spaced apart on the sidewall of the first liquid storage tank 100. The first opening 110 communicates with the first inlet and is provided with a first liquid pump 710 in the communication passage. The second opening 120 communicates with the first inlet and is provided with a liquid return valve 930 in the communication passage.

[0072] In this way, during the power generation process of the above-mentioned high-voltage energy storage power generation system 10, when the piston member 412 slides to the end of the cylinder body 411 where the second inlet is provided to push the second liquid in the second chamber 412 to the hydraulic drive mechanism 500, the first liquid inlet valve 430 and the second liquid outlet valve 460 are opened, and the first liquid outlet valve 440 and the second liquid inlet valve 450 are closed. At the same time, the second liquid pump 720 operates to suck the liquid in the second liquid storage tank 200 into the second chamber 412, so as to use the piston member 412 to push the first liquid in the first chamber 411 through the second opening 120 to the first liquid storage tank 100, thereby realizing the reflux of the first liquid.

[0073] When there are multiple piston cylinders 400, the first opening 110 is connected to the multiple first inlets, and a first liquid pump 710 is provided on the communication path. The second opening 120 is connected to the multiple first inlets, and a liquid return valve 930 is provided on the communication path.

[0074] Of course, in other embodiments, the reflux of the first liquid during the power generation process may also be achieved by reversing the first liquid pump 710 .

[0075] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0076] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be determined by the appended claims.

Claims

1. A high-voltage energy storage power generation system, characterized in that: It includes a first liquid storage tank, a second liquid storage tank, a high-pressure energy storage tank, a piston cylinder, a hydraulic drive mechanism, a power generation device and a control device connected to the hydraulic drive mechanism; The piston cylinder includes a hollow cylinder body and a piston member slidably mounted in the cylinder body; the piston member divides the space in the cylinder body into a first chamber and a second chamber; a first inlet and a first outlet communicating with the first chamber are formed at one end of the cylinder body, and a second inlet and a second outlet communicating with the second chamber are formed at the other end; The first inlet is connected to the first liquid storage tank via a first liquid inlet valve and a first liquid pump in sequence; the first outlet is connected to the high-pressure accumulator tank via a first liquid outlet valve; the second inlet is connected to the liquid inlet of the hydraulic drive mechanism and the outlet of the second liquid pump respectively via a second liquid inlet valve; the inlet of the second liquid pump is connected to the second liquid storage tank; the second outlet is connected to the liquid outlet of the hydraulic drive mechanism and the second liquid storage tank respectively via a second liquid outlet valve; There are multiple piston cylinders; each first inlet is connected to the outlet of the first liquid pump through the first liquid inlet valve; the inlet of the first liquid pump is connected to the first liquid storage tank; each first outlet is connected to the high-pressure accumulator tank through the first liquid outlet valve; each second inlet is connected to the liquid inlet of the hydraulic drive mechanism and the outlet of the second liquid pump respectively through the second liquid inlet valve; each second outlet is connected to the liquid outlet of the hydraulic drive mechanism and the second liquid storage tank respectively through the second liquid outlet valve; The control device is used to control the opening and closing of the plurality of first liquid inlet valves, the plurality of first liquid outlet valves, the plurality of second liquid inlet valves, and the plurality of second liquid outlet valves according to preset instructions, so that the sliding direction of some of the piston members is opposite to the sliding direction of the remaining piston members; The side wall of the first liquid storage tank is spaced apart with a first opening and a second opening; the first opening is connected to the first inlet, and the first liquid pump is provided on the connecting passage; the second opening is connected to the first inlet, and a liquid return valve is provided on the connecting passage.

2. The high-voltage energy storage power generation system according to claim 1, characterized in that: It also includes a first low-pressure pipeline, a first high-pressure pipeline, a second low-pressure pipeline, and a second high-pressure pipeline; The first low-pressure pipeline includes a first low-pressure main pipe and a plurality of first low-pressure branch pipes; one end of the first low-pressure main pipe is connected to the first liquid storage tank, and the other end is connected to each of the plurality of first low-pressure branch pipes; one end of each of the plurality of first low-pressure branch pipes, which is remote from the first low-pressure main pipe, is connected to each of the plurality of first inlets in a one-to-one correspondence; the first liquid pump is disposed on the first low-pressure main pipe; and each of the first low-pressure branch pipes is provided with a first liquid inlet valve; The first high-pressure pipeline includes a first high-pressure main pipe and a plurality of first high-pressure branch pipes; one end of the first high-pressure main pipe is connected to the high-pressure accumulator tank, and the other end is connected to each of the plurality of first high-pressure branch pipes; ends of the plurality of first high-pressure branch pipes remote from the first high-pressure main pipe are connected to each of the plurality of first outlets in a one-to-one correspondence; each of the first high-pressure branch pipes is provided with a first liquid outlet valve; The second low-pressure pipeline includes a second low-pressure main pipe and a plurality of second low-pressure branch pipes; the two ends of the second low-pressure main pipe are respectively connected to the liquid outlet of the hydraulic drive mechanism and the second liquid storage tank; one end of each of the second low-pressure branch pipes is respectively connected to the plurality of second outlets in a one-to-one correspondence, and the other end is all connected to the second low-pressure main pipe; each of the second low-pressure branch pipes is provided with a second liquid outlet valve; and a back-pressure valve is provided at one end of the second low-pressure main pipe close to the second liquid storage tank. The second high-pressure pipeline includes a second high-pressure main pipe and multiple second high-pressure branch pipes; the two ends of the second high-pressure main pipe are respectively connected to the liquid inlet of the hydraulic drive mechanism and the second liquid storage tank; one end of the multiple second high-pressure branch pipes is respectively connected to the multiple second inlets one by one, and the other ends are all connected to the second high-pressure main pipe; each of the second high-pressure branch pipes is provided with the second liquid inlet valve; the second liquid pump and the one-way valve are provided at the end of the second high-pressure main pipe close to the second liquid storage tank.

3. The high-voltage energy storage power generation system according to claim 1, characterized in that: It also includes a heat insulator; the heat insulator is laterally and slidably arranged in the high-pressure energy storage tank, and is used to separate the gas and liquid in the high-pressure energy storage tank.

4. The high-voltage energy storage power generation system according to claim 1, characterized in that: A heat insulation layer is formed on the outer surface of the high-pressure energy storage tank.

5. The high-voltage energy storage power generation system according to claim 1, characterized in that: The first liquid pump is a water pump; the second liquid pump is an oil pump; the hydraulic drive mechanism is a hydraulic motor; the power generation device includes a gearbox transmission-connected to the hydraulic motor and a generator transmission-connected to the gearbox.

6. The high-voltage energy storage power generation system according to claim 5, characterized in that: The hydraulic motor is a variable motor; the high-voltage energy storage power generation system also includes a controller and a speed sensor; the speed sensor is communicatively connected to the controller and is used to obtain the output speed of the variable motor in real time; the controller is electrically connected to the variable motor and is used to adaptively adjust the displacement of the variable motor according to the output speed so that the variable motor can output at a constant speed.

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