Flexible air adjusting type compressed air energy storage system and using method

Abstract

The invention relates to the technical field of energy storage, in particular to a flexible air adjusting type compressed air energy storage system and a using method. A flexible air adjusting type compressed air energy storage system comprises a compressor assembly which comprises a first compressor, a second compressor, a first air outlet pipeline and a second air outlet pipeline, the first compressor and the second compressor are connected in series, and the first air outlet pipeline is arranged between the air outlet end of the first compressor and the air inlet end of the second compressor; a second air outlet pipeline is arranged at the air outlet end of the second compressor; the flexible gas storage assembly comprises a first gas inlet branch pipe, a first flexible gas storage tank, a second gas inlet branch pipe and a second flexible gas storage tank. The invention provides a flexible air adjusting type compressed air energy storage system and a use method, and aims to solve the problems that the volume of an air storage tank is not changed, air is difficult to compress and convey into the air storage tank after a certain volume of air is contained in the air storage tank, a compressor is always in a working condition changing state, and the service life of the air storage tank is prolonged. And the efficiency of the compressor is lower than that of operation under the rated working condition.

Description

Technical Field

[0001] The present invention relates to the field of energy storage technology, and in particular to a flexible gas-regulated compressed air energy storage system and a method of using the same. Background Art

[0002] Compressed Air Energy Storage (CAES) is a physical energy storage technology that compresses air during off-peak periods to store energy and releases it during peak hours to generate electricity. Its core principles include the following: During the energy storage phase, electricity is used to drive a multi-stage compressor, compressing air to high pressure and storing it in underground salt caverns, artificial chambers, or air tanks. The electrical energy is converted into pressure and thermal energy in the air. During the energy release phase, the high-pressure air is converted into mechanical energy through an expander (turbine) to drive a generator for power generation.

[0003] During the operation of the compressor, the compressor compresses the gas in the environment and then stores it in a gas tank. However, the existing gas tank has a constant volume, and the gas will be slowly filled into the gas tank. After accommodating a certain volume of gas, it will become difficult to compress and transport the gas into the gas tank. During the entire charging process, the compressor is always in a state of changing operating conditions (also known as "variable operating conditions"), resulting in the compressor efficiency being lower than the efficiency of rated operating conditions. Summary of the Invention

[0004] In view of this, the present invention provides a flexible gas-regulated compressed air energy storage system and a method of use to solve the problem that the existing gas tank has a constant volume and is slowly filled with gas. After accommodating a certain volume of gas, it becomes difficult to compress and transport the gas into the gas tank. During the entire inflation process, the compressor is always in a state of changing operating conditions (also known as a "variable operating condition state"), resulting in the problem that the compressor efficiency is lower than the efficiency of the rated operating condition.

[0005] In a first aspect, the present invention provides a flexible gas-regulated compressed air energy storage system, comprising:

[0006] A compressor assembly, the compressor assembly comprising a first compressor, a second compressor, a first air outlet pipeline, and a second air outlet pipeline, the first compressor and the second compressor being arranged in series, the first air outlet pipeline being provided between the air outlet end of the first compressor and the air inlet end of the second compressor, and the second air outlet pipeline being provided at the air outlet end of the second compressor;

[0007] A flexible air storage assembly, the flexible air storage assembly includes a first air intake branch, a first flexible air storage tank, a second air intake branch, and a second flexible air storage tank, one end of the first air intake branch is connected to the first air outlet pipeline, and the other end of the first air intake branch is connected to the first flexible air storage tank, one end of the second air intake branch is connected to the second air outlet pipeline, and the other end of the second air intake branch is connected to the second flexible air storage tank.

[0008] By setting up the first flexible gas storage tank and the second flexible gas storage tank, the first compressor and the second compressor can deliver constant pressure gas under constant operating conditions under their own rated operating conditions, that is, the outlet pressure of the compressor is maintained as constant as possible near the design point (peak operating point). Compared with the state of variable operating conditions, it has the advantage of high working efficiency. At the same time, the constant operating conditions facilitate extending the overall life of the compressor.

[0009] In an optional embodiment, the compressor assembly also includes a third compressor and a third air outlet pipeline, the flexible air storage assembly also includes a third flexible air storage tank, a second air outlet pipeline is provided between the second compressor and the third compressor, and the third air outlet pipeline is provided between the third compressor and the third flexible air storage tank.

[0010] In an optional embodiment, a heat exchange component is further included, which includes a heat exchange component including a heat storage tank, a first heat exchanger, a second heat exchanger, a heat outlet main pipe, a heat inlet main pipe, a first heat exchange branch pipe, a second heat exchange branch pipe, a connecting pipe, a first heat inlet pipe and a first heat outlet pipe, the first heat exchange branch pipe and the first air outlet pipe are respectively arranged through the first heat exchanger, the second heat exchange branch pipe and the second air outlet pipe are respectively arranged through the second heat exchanger, one end of the heat outlet main pipe is connected to the heat storage tank, the other end of the heat outlet main pipe is connected to the connecting pipe, the connecting pipe is connected to the first heat inlet pipe, the two ends of the first heat exchange branch pipe are respectively connected to the first heat inlet pipe and the first heat outlet pipe, the two ends of the second heat exchange branch pipe are respectively connected to the first heat inlet pipe and the first heat outlet pipe, and the heat inlet main pipe is respectively connected to the heat storage tank and the first heat outlet pipe.

[0011] In an optional embodiment, the heat exchange component also includes a third heat exchanger and a third heat exchange branch pipe. The third heat exchange branch pipe and the third air outlet pipe are respectively arranged through the third heat exchanger, and the two ends of the third heat exchange branch pipe are respectively connected to the first heat inlet pipe and the first heat outlet pipe.

[0012] In an optional embodiment, an expansion assembly is further included, which includes a first expander, a second expander, a first air intake pipeline and a second air intake pipeline. The first air intake pipeline is provided between the first expander and the third flexible air storage tank, and the second air intake pipeline is provided between the first expander and the second expander.

[0013] In an optional embodiment, the flexible air storage assembly also includes a first air outlet branch pipe and a first flow control valve, one end of the first air outlet branch pipe is connected to the second flexible air storage tank, the other end of the first air outlet branch pipe is connected to the second air inlet pipeline, and a first flow control valve is provided on the first air outlet branch pipe.

[0014] In an optional embodiment, the flexible air storage assembly also includes a second air outlet branch and a second flow control valve, and the expansion assembly also includes a third expander and a third air inlet pipeline. A third air inlet pipeline is provided between the second expander and the third expander. One end of the second air outlet branch is connected to the first flexible air storage tank, and the other end of the second air outlet branch is connected to the third air inlet pipeline. A second flow control valve is provided on the second air outlet branch.

[0015] In an optional embodiment, the heat exchange assembly also includes a fourth heat exchanger, a fifth heat exchanger, a second heat inlet pipe, a second heat outlet pipe, a fourth heat exchange branch pipe and a fifth heat exchange branch pipe, one end of the second heat inlet pipe is connected to the heat outlet main pipe, the other end of the second heat inlet pipe is connected to the connecting pipe, the fourth heat exchange branch pipe and the first air intake pipe respectively pass through the fourth heat exchanger, the fifth heat exchange branch pipe and the second air intake pipe respectively pass through the fifth heat exchanger, the two ends of the fourth heat exchange branch pipe are respectively connected to the second heat inlet pipe and the second heat outlet pipe, the two ends of the fifth heat exchange branch pipe are respectively connected to the second heat inlet pipe and the second heat outlet pipe, and the second heat outlet pipe is connected to the connecting pipe.

[0016] In an optional embodiment, the heat exchange component also includes a first connecting branch, a second connecting branch, a third connecting branch, a fourth connecting branch, a first heat exchange control valve, a second heat exchange control valve, a third heat exchange control valve and a fourth heat exchange control valve, the first connecting branch is respectively connected to the first heat inlet pipe and the connecting pipe, the first connecting branch is provided with a first heat exchange control valve, the second connecting branch is respectively connected to the first heat outlet pipe and the connecting pipe, the second connecting branch is provided with a second heat exchange control valve, the third connecting branch is respectively connected to the second heat inlet pipe and the connecting pipe, the third connecting branch is provided with a third heat exchange control valve, the fourth connecting branch is respectively connected to the second heat outlet pipe and the connecting pipe, and the fourth connecting branch is provided with a fourth heat exchange control valve.

[0017] In the second aspect, the present invention also provides a method for using a flexible air-regulating compressed air energy storage system. In the energy storage state, the first compressor generates a first pressure gas that enters the first air outlet pipeline. A part of the first pressure gas in the first air outlet pipeline enters the second compressor, and another part of the first pressure gas enters the first flexible air storage tank through the first air inlet branch; the first pressure gas entering the second compressor is compressed by the second compressor and becomes a second pressure gas that enters the second air outlet pipeline. A part of the second pressure gas in the second air outlet pipeline enters the second compressor, and another part of the second pressure gas enters the second flexible air storage tank through the second air inlet branch. The first pressure value is less than the second pressure value. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0019] Figure 1 Schematic diagram of a flexible gas-regulated compressed air energy storage system according to an embodiment of the present invention;

[0020] Figure 2 A schematic diagram of the connection between a compressor assembly and a flexible gas storage assembly according to an embodiment of the present invention;

[0021] Figure 3 A schematic diagram of the connection between an expansion assembly and a flexible gas storage assembly according to an embodiment of the present invention;

[0022] Figure 4 Schematic diagram of the connection of heat exchange components according to an embodiment of the present invention.

[0023] Explanation of reference numerals: 1. compressor assembly; 101. first compressor; 102. second compressor; 103. third compressor; 104. first air outlet pipeline; 105. second air outlet pipeline; 106. third air outlet pipeline; 107. fourth air inlet pipeline; 108. gas control valve; 2. flexible gas storage assembly; 201. first flexible gas storage tank; 202. second flexible gas storage tank; 203. third flexible gas storage tank; 204. first air inlet branch pipe; 205. second air inlet branch pipe Branch pipe; 206, first gas transmission branch pipe; 207, second gas transmission branch pipe; 208, first gas outlet branch pipe; 209, second gas outlet branch pipe; 210, first flow control valve; 211, second flow control valve; 212, first external transmission pipeline; 213, second external transmission pipeline; 3, heat exchange assembly; 301, first heat exchanger; 302, second heat exchanger; 303, third heat exchanger; 304, fourth heat exchanger; 305, fifth heat exchanger; 306, sixth heat exchanger; 307 , heat storage tank; 308, heat outlet main pipe; 309, connecting pipe; 310, heat inlet main pipe; 311, first heat inlet pipe; 312, first heat outlet pipe; 313, second heat inlet pipe; 314, second heat outlet pipe; 315, first connecting branch pipe; 316, first heat exchange control valve; 317, second connecting branch pipe; 318, second heat exchange control valve; 319, third connecting branch pipe; 320, third heat exchange control valve; 321, fourth connecting branch pipe; 322, fourth heat exchange control valve; 323. First heat exchange branch; 324. Second heat exchange branch; 325. Third heat exchange branch; 326. Fourth heat exchange branch; 327. Fifth heat exchange branch; 328. Sixth heat exchange branch; 329. Power pump; 330. Main control valve; 4. Expansion assembly; 401. First expander; 402. Second expander; 403. Third expander; 404. First air inlet pipeline; 405. Second air inlet pipeline; 406. Third air inlet pipeline; 407. Fourth air outlet pipeline. DETAILED DESCRIPTION

[0024] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative efforts shall fall within the scope of protection of the present invention.

[0025] The following combination Figures 1 to 4 , describing embodiments of the present invention.

[0026] According to an embodiment of the present invention, on the one hand, a flexible air-regulated compressed air energy storage system is provided, comprising: a compressor assembly 1, comprising a first compressor 101, a second compressor 102, a first air outlet pipeline 104, and a second air outlet pipeline 105, wherein the first compressor 101 and the second compressor 102 are arranged in series, the first air outlet pipeline 104 is provided between the air outlet end of the first compressor 101 and the air inlet end of the second compressor 102, and the second air outlet pipeline 105 is provided at the air outlet end of the second compressor 102;

[0027] The flexible air storage assembly 2 includes a first air intake branch pipe 204, a first flexible air storage tank 201, a second air intake branch pipe 205, and a second flexible air storage tank 202. One end of the first air intake branch pipe 204 is connected to the first air outlet pipeline 104, and the other end of the first air intake branch pipe 204 is connected to the first flexible air storage tank 201. One end of the second air intake branch pipe 205 is connected to the second air outlet pipeline 105, and the other end of the second air intake branch pipe 205 is connected to the second flexible air storage tank 202.

[0028] In the energy storage state, the first compressor 101 generates a first pressure gas which enters the first air outlet pipeline 104. A part of the first pressure gas in the first air outlet pipeline 104 enters the second compressor 102, and another part of the first pressure gas enters the first flexible gas storage tank 201 through the first air inlet branch 204; the first pressure gas entering the second compressor 102 is compressed by the second compressor 102 and becomes a second pressure gas which enters the second air outlet pipeline 105. A part of the second pressure gas in the second air outlet pipeline 105 enters the second compressor 102, and another part of the second pressure gas enters the second flexible gas storage tank 202 through the second air inlet branch 205. The first pressure value is less than the second pressure value.

[0029] By setting up the first flexible gas storage tank 201 and the second flexible gas storage tank 202, the first compressor 101 and the second compressor 102 can deliver constant pressure gas under constant operating conditions under their own rated operating conditions, that is, the outlet pressure of the compressor is maintained as constant as possible near the design point (peak operating point). Compared with the state of variable operating conditions, it has the advantage of high working efficiency. At the same time, the constant operating conditions facilitate extending the overall life of the compressor.

[0030] In one embodiment, Figure 1 、 Figure 2As shown, the compressor assembly 1 also includes a third compressor 103 and a third air outlet pipeline 106, and the flexible air storage assembly 2 also includes a third flexible air storage tank 203. A second air outlet pipeline 105 is provided between the second compressor 102 and the third compressor 103, and the third air outlet pipeline 106 is provided between the third compressor 103 and the third flexible air storage tank 203. The second air outlet pipeline 105 inputs the second pressure gas into the third compressor 103, and the third compressor 103 compresses the second pressure gas into the third pressure gas. The third pressure gas enters the third flexible air storage tank 203 through the third air outlet pipeline 106, and the third pressure value is greater than the second pressure value. It should be noted that the inner diameter of the first air outlet pipeline 104 is greater than the inner diameter of the second air outlet pipeline 105, and the inner diameter of the second air outlet pipeline 105 is greater than the inner diameter of the third air outlet pipeline 106. It should be noted that the first flexible gas storage tank 201 , the second flexible gas storage tank 202 , and the third flexible gas storage tank 203 in this embodiment are gas storage tanks with constant internal pressure and variable volume.

[0031] In one embodiment, Figure 1 、 Figure 2 As shown, the heat exchange assembly 3 is also included, and the heat exchange assembly 3 includes a heat storage tank 307, a first heat exchanger 301, a second heat exchanger 302, a heat outlet main pipe 308, a heat inlet main pipe 310, a first heat exchange branch pipe 323, a second heat exchange branch pipe 324, a connecting pipe 309, a first heat inlet pipe 311 and a first heat outlet pipe 312. The first heat exchange branch pipe 323 and the first outlet pipe 104 are respectively provided through the first heat exchanger 301, and the second heat exchange branch pipe 324 and the second outlet pipe 105 are respectively provided through the second heat exchanger. The heat exchanger 302 is provided with one end of a heat outlet main pipe 308 being connected to the heat storage tank 307, and the other end of the heat outlet main pipe 308 being connected to a connecting pipe 309, the connecting pipe 309 being connected to the first heat inlet pipe 311, the two ends of the first heat exchange branch pipe 323 being connected to the first heat inlet pipe 311 and the first heat outlet pipe 312 respectively, the two ends of the second heat exchange branch pipe 324 being connected to the first heat inlet pipe 311 and the first heat outlet pipe 312 respectively, and the heat inlet main pipe 310 being connected to the heat storage tank 307 and the first heat outlet pipe 312 respectively. The heat storage tank 307 contains a flowing heat exchange medium, which flows out of the heat storage tank 307 after heat exchange, passes through the heat outlet main pipe 308, the connecting pipe 309, and the first heat inlet pipe 311 in sequence, and then enters the first heat exchange branch pipe 323 and the second heat exchange branch pipe 324 respectively. The heat exchange medium exchanges heat with the first pressure gas in the first gas outlet pipeline 104 in the first heat exchanger 301, thereby reducing the temperature of the first pressure gas. The heat exchange medium exchanges heat with the second pressure gas in the second gas outlet pipeline 105 in the second heat exchanger 302, thereby reducing the temperature of the second pressure gas. After heat exchange, the heat exchange medium converges into the first heat outlet pipe 312, and then enters the heat inlet main pipe 310 from the first heat outlet pipe 312 and flows into the heat storage tank 307.

[0032] In one embodiment, Figure 1 、 Figure 2 and Figure 4 As shown, the heat exchange assembly 3 further includes a third heat exchanger 303 and a third heat exchange branch 325. The third heat exchange branch 325 and the third outlet pipe 106 are respectively disposed through the third heat exchanger 303. The ends of the third heat exchange branch 325 are connected to the first heat inlet pipe 311 and the first heat outlet pipe 312, respectively. The heat exchange medium in the first heat inlet pipe 311 flows into the third heat exchange branch 325. Within the third heat exchanger 303, the heat exchange medium exchanges heat with the third pressure gas in the third outlet pipe 106, reducing the temperature of the third pressure gas. After heat exchange, the heat exchange medium flows into the first heat outlet pipe 312. It should be noted that in this embodiment, the heat exchange medium is water and the gas is air.

[0033] In one embodiment, Figure 1 、 Figure 3 As shown, the system also includes an expansion assembly 4, which includes a first expander 401, a second expander 402, a first air inlet line 404, and a second air inlet line 405. The first air inlet line 404 is located between the first expander 401 and the third flexible air storage tank 203, while the second air inlet line 405 is located between the first expander 401 and the second expander 402. A continuous flow of third-pressure gas is provided from the third flexible air storage tank 203, passing through the first air inlet line 404 to continuously drive the first expander 401 to perform work. The third-pressure gas is then reduced to a fourth-pressure gas after passing through the first expander 401. This gas enters the second expander 402 through the second air inlet line 405, driving the second expander 402 to perform work. It should be noted that the pressure of the fourth-pressure gas is slightly lower than the second pressure, but greater than the first pressure.

[0034] In one embodiment, Figure 1 、 Figure 3 As shown, the flexible gas storage assembly 2 further includes a first outlet branch pipe 208 and a first flow control valve 210. One end of the first outlet branch pipe 208 is connected to the second flexible gas storage tank 202, and the other end of the first outlet branch pipe 208 is connected to the second gas inlet pipeline 405. The first flow control valve 210 is provided on the first outlet branch pipe 208. The second pressurized gas stored in the second flexible gas storage tank 202 flows into the second gas inlet pipeline 405 through the first outlet branch pipe 208, thereby driving the second expander 402 to generate work. The gas flow in the first outlet branch pipe 208 is controlled by the first flow control valve 210. Specifically, the first flow control valve 210 is an electromagnetic flow control valve.

[0035] In one embodiment, Figure 1 、 Figure 3As shown, the flexible gas storage assembly 2 also includes a second outlet branch 209 and a second flow control valve 211. The expansion assembly 4 also includes a third expander 403 and a third inlet pipeline 406. The third inlet pipeline 406 is interposed between the second expander 402 and the third expander 403. One end of the second outlet branch 209 is connected to the first flexible gas storage tank 201, and the other end of the second outlet branch 209 is connected to the third inlet pipeline 406. The second outlet branch 209 is provided with a second flow control valve 211. The first pressurized gas stored in the first flexible gas storage tank 201 flows into the third inlet pipeline 406 through the second outlet branch 209, thereby driving the third expander 403 to generate power. The gas flow in the second outlet branch 209 is controlled by the second flow control valve 211. Specifically, the second flow control valve 211 is an electromagnetic flow control valve.

[0036] In order to facilitate the replenishment of the gas in the first flexible gas storage tank 201 and the second flexible gas storage tank 202, as shown in FIG. Figure 1 、 Figure 2 and Figure 3 As shown, a first gas branch pipe 206 is provided between the first flexible gas storage tank 201 and the second flexible gas storage tank 202, so that the gas in the second flexible gas storage tank 202 flows into the first flexible gas storage tank 201; a second gas branch pipe 207 is provided between the second flexible gas storage tank 202 and the third flexible gas storage tank 203, so that the gas in the third flexible gas storage tank 203 flows into the second flexible gas storage tank 202.

[0037] In one embodiment, Figure 1 、 Figure 3 and Figure 4As shown, the heat exchange component 3 also includes a fourth heat exchanger 304, a fifth heat exchanger 305, a second heat inlet pipe 313, a second heat outlet pipe 314, a fourth heat exchange branch pipe 326 and a fifth heat exchange branch pipe 327. One end of the second heat inlet pipe 313 is connected to the heat outlet main pipe 308, and the other end of the second heat inlet pipe 313 is connected to the connecting pipe 309. The fourth heat exchange branch pipe 326 and the first air intake pipe 404 are respectively arranged to pass through the fourth heat exchanger 304. The fifth heat exchange branch pipe 327 and the second air intake pipe 405 are respectively arranged to pass through the fifth heat exchanger 305. Both ends of the fourth heat exchange branch pipe 326 are respectively connected to the second heat inlet pipe 313 and the second heat outlet pipe 314. Both ends of the fifth heat exchange branch pipe 327 are respectively connected to the second heat inlet pipe 313 and the second heat outlet pipe 314. The second heat outlet pipe 314 is connected to the connecting pipe 309. The heat exchange medium in the heat outlet main pipe 308 flows into the second heat inlet pipe 313, and flows into the fourth heat exchange branch pipe 326 and the fifth heat exchange branch pipe 327 respectively from the second heat inlet pipe 313. The heat exchange medium enters the fourth heat exchanger 304 through the fourth heat exchange branch pipe 326 to provide heat for the gas in the first air inlet pipe 404 to increase the gas temperature. The heat exchange medium enters the fifth heat exchanger 305 through the fifth heat exchange branch pipe 327 to provide heat for the gas in the second air inlet pipe 405 to increase the gas temperature. After heat exchange, the heat exchange medium converges and flows into the second heat outlet pipe 314, and flows into the connecting pipe 309 from the second heat outlet pipe 314.

[0038] In this embodiment, if Figure 1 、 Figure 3 and Figure 4 As shown, the heat exchange assembly 3 also includes a sixth heat exchanger 306 and a sixth heat exchange branch 328. The two ends of the sixth heat exchange branch 328 are respectively connected to the second heat inlet pipe 313 and the second heat outlet pipe 314. The sixth heat exchange branch 328 and the third air inlet pipe 406 are respectively set to pass through the sixth heat exchanger 306. The heat exchange medium enters the sixth heat exchanger 306 through the sixth heat exchange branch 328 to provide heat for the gas in the third air inlet pipe 406 to increase the gas temperature. It should be noted that, as Figure 1 、 Figure 2 、 Figure 3 As shown, the compressor assembly 1 also includes a fourth air inlet pipeline 107, which is arranged at the air inlet end of the first compressor 101; the expansion assembly 4 also includes a fourth air outlet pipeline 407, which is arranged at the air outlet end of the third expander 403.

[0039] In this embodiment, if Figure 1 、 Figure 4As shown, the heat exchange component 3 also includes a first connecting branch pipe 315, a second connecting branch pipe 317, a third connecting branch pipe 319, a fourth connecting branch pipe 321, a first heat exchange control valve 316, a second heat exchange control valve 318, a third heat exchange control valve 320 and a fourth heat exchange control valve 322. The first connecting branch pipe 315 is respectively connected to the first heat inlet pipe 311 and the connecting pipe 309, and the first heat exchange control valve 316 is provided on the first connecting branch pipe 315. The second connecting branch pipe 317 is respectively connected to the first heat outlet pipe 312 and the connecting pipe 309, and the second connecting branch pipe 317 is provided with the second heat exchange control valve 318. The third connecting branch pipe 319 is respectively connected to the second heat inlet pipe 313 and the connecting pipe 309, and the third connecting branch pipe 319 is provided with the third heat exchange control valve 320. The fourth connecting branch pipe 321 is respectively connected to the second heat outlet pipe 314 and the connecting pipe 309, and the fourth connecting branch pipe 321 is provided with the fourth heat exchange control valve 322. The first heat inlet pipe 311 is connected to the connecting pipe 309 via a first connecting branch pipe 315, and a first heat exchange control valve 316 controls the opening and closing of the first connecting branch pipe 315. The second connecting branch pipe 317 is connected to the second heat inlet pipe 313 and the connecting pipe 309, and a second heat exchange control valve 318 controls the opening and closing of the second connecting branch pipe 317. The third connecting branch pipe 319 is connected to the third heat inlet pipe and the connecting pipe 309, and a third heat exchange control valve 320 controls the opening and closing of the third connecting branch pipe 319. The fourth connecting branch pipe 321 is connected to the fourth heat inlet pipe and the connecting pipe 309, and a fourth heat exchange control valve 322 controls the opening and closing of the fourth connecting branch pipe 321. It should be noted that the first heat exchange control valve 316, the second heat exchange control valve 318, the third heat exchange control valve 320, and the fourth heat exchange control valve 322 are all electromagnetic control valves.

[0040] To achieve pipeline control, such as Figure 1 、 Figure 2 、 Figure 3 and Figure 4 As shown, the first outlet branch pipe 208, the second outlet branch pipe 209, the third outlet pipeline 106, the first gas supply branch pipe 206, the second gas supply branch pipe 207, the first intake branch pipe 204, and the second intake branch pipe 205 are each equipped with a gas control valve 108. The heat outlet main pipe 308 is equipped with a master control valve 330. Specifically, the gas control valve 108 is a solenoid-operated control valve. It should be noted that the gas control valve 108 of the first intake branch pipe 204 is located upstream of the first flow control valve 210, the gas control valve 108 of the second intake branch pipe 205 is located upstream of the second flow control valve 211, and the master control valve 330 of the heat outlet main pipe 308 is located upstream of the power pump 329. In this embodiment, the upstream refers to the place where the gas or liquid flows first. For example, "the main control valve 330 of the heat outlet main pipe 308 is located upstream of the power pump 329" means that the heat exchange medium flowing out of the heat storage tank 307 first flows through the main control valve 330 and then flows through the power pump 329.

[0041] To achieve automatic control, a controller is also included, which is respectively connected to the first flow control valve 210, the second flow control valve 211, the power pump 329, the first heat exchange control valve 316, the second heat exchange control valve 318, the third heat exchange control valve 320, the fourth heat exchange control valve 322, the main control valve 330, and all the gas control valves 108.

[0042] The flexible air-regulating compressed air energy storage system provided by the present invention has two states: energy storage and energy release. The energy storage state refers to when the power grid has excess electricity, the compressor works to absorb the excess electricity generated by wind energy, solar energy, power plants, etc.; the energy release state refers to when the power grid is insufficient, the expander works to provide electricity to the grid.

[0043] A method for using a flexible gas-regulated compressed air energy storage system, in an energy storage state, comprises the following steps:

[0044] (1) Gas enters the fourth air inlet pipe 107, and becomes first-pressure gas after passing through the first compressor 101. The gas control valve 108 of the first air inlet branch pipe 204 is opened, and the first air outlet pipe delivers a portion of the first-pressure gas to the second compressor 102, and another portion of the first-pressure gas to the first flexible air storage tank 201; the first-pressure gas enters the second compressor 102 and is compressed into second-pressure gas. The gas control valve 108 of the second air inlet branch pipe 205 is opened, and the second air outlet pipe delivers a portion of the second-pressure gas to the third compressor 103, and another portion of the second-pressure gas to the second flexible air storage tank 202; the second-pressure gas enters the third compressor 103 and is compressed into third-pressure gas. The third-pressure gas enters the third flexible air storage tank 203 through the third air outlet pipe 106;

[0045] (2) At the same time, the main control valve 330, the first heat exchange control valve 316 and the third heat exchange control valve 320 are opened. Driven by the power pump 329, the heat exchange medium in the heat storage tank 307 passes through the heat outlet main pipe 308, the second heat inlet pipe 313, the third connecting branch pipe 319, the connecting pipe 309, the first connecting branch pipe 315, and the first heat inlet pipe 311 in sequence, and enters the first heat exchange branch pipe 323, the second heat exchange branch pipe 324 and the third heat exchange branch pipe 325 respectively from the first heat inlet pipe 311. The heat exchange medium absorbs the heat of the gas in the first outlet pipe 104 in the first heat exchanger 301, absorbs the heat of the gas in the second outlet pipe 105 in the second heat exchanger 302, and absorbs the heat of the gas in the third outlet pipe 106 in the third heat exchanger 303. After absorbing the heat, the heat exchange medium flows into the first heat outlet pipe 312 and finally flows into the heat storage tank 307 through the heat inlet main pipe 310.

[0046] It should be noted that, during the energy storage process, except for the aforementioned valves being open, all other valves are closed, and the expansion assembly 4 is closed. Steps (1) and (2) are performed simultaneously, and the first flexible gas storage tank 201, the second flexible gas storage tank 202, and the third flexible gas storage tank 203 respectively store gases of different pressures that are approximately constant pressure. In addition, during the energy storage process, the first compressor 101, the second compressor 102, and the third compressor 103 are all operated in a constant state close to their own operating peak points.

[0047] A method for using a flexible gas-regulated compressed air energy storage system, in an energy-releasing state, comprises the following steps:

[0048] (1) The third flexible gas storage tank 203 continuously delivers a third pressure gas at a constant pressure to the first expander 401 through the first gas inlet line 404 to drive the first expander 401 to generate power; the third pressure gas is converted into a fourth pressure gas after passing through the first expander 401, and the fourth pressure gas enters the second expander 402 through the second gas inlet line 405. The gas control valve 108 and the first flow control valve 210 on the first gas outlet branch 208 are opened, so that the second pressure gas continuously delivered by the second flexible gas storage tank 202 enters the second expander 402 through the second gas inlet line 405. 2, so as to drive the second expander 402 to generate power; the gas after passing through the second expander 402 becomes fifth-pressure gas, which enters the third expander 403 through the third air inlet pipeline 406, and the gas control valve 108 and the second flow control valve 211 on the second air outlet branch pipe 209 are opened, so that the first-pressure gas continuously delivered by the first flexible air storage tank 201 enters the third expander 403 through the third air inlet pipeline 406, so as to drive the third expander 403 to generate power, and the gas passing through the third expander 403 is discharged into the environment through the fourth air outlet pipeline 407;

[0049] (2) At the same time, the main control valve 330, the second heat exchange control valve 318 and the fourth heat exchange control valve 322 are opened, and the power pump 329 drives the heat exchange medium so that the heat exchange medium flows through the heat outlet main pipe 308 and the second heat inlet pipe 313 in sequence and flows into the fourth heat exchange branch pipe 326, the fifth heat exchange branch pipe 327 and the sixth heat exchange branch pipe 328 respectively. The heat exchange medium releases heat in the fourth heat exchange branch pipe 326 to increase the gas temperature in the first intake pipe 404, and releases heat in the fifth heat exchange branch pipe 327 to increase the gas temperature in the first intake pipe 404. The heat exchange medium releases heat in the sixth heat exchange branch 328 to increase the temperature of the gas in the third air intake pipeline 406. After releasing the heat, the heat exchange medium flows into the second heat outlet pipe 314 and enters the connecting pipe 309 through the fourth connecting branch 321. The heat exchange medium in the connecting pipe 309 enters the first heat outlet pipe 312 through the second connecting branch 317, flows into the heat inlet main pipe 310 through the first heat outlet pipe 312, and finally flows back to the heat storage tank 307.

[0050] It should be noted that, during the energy release process, except for the aforementioned valves being open, all other valves are closed, and the compressor assembly 1 is closed. Steps (1) and (2) are performed simultaneously, and gases of different pressures approximately at constant pressure are released from the first flexible gas storage tank 201, the second flexible gas storage tank 202, and the third flexible gas storage tank 203. During the energy storage process, the first expander 401, the second expander 402, and the third expander 403 are all operated in a constant state close to their own operating peak points.

[0051] In this embodiment, in order to replenish the gas in the first flexible gas storage tank 201 or the second flexible gas storage tank 202, as shown in FIG. Figure 1 、 Figure 2 and Figure 3 As shown, the gas control valve 108 on the first gas branch pipe 206 is opened to enable gas to be supplied from the second flexible gas tank 202 to the first flexible gas tank 201; the gas control valve 108 on the second gas branch pipe 207 is opened to enable gas to be supplied from the third flexible gas tank 203 to the second flexible gas tank 202. To ensure a continuous supply of heat to the heat storage tank 307, a heating pipe is provided in the heat storage tank 307 of this embodiment to replenish heat to the heat storage tank 307 in the event of an extreme operating condition of insufficient heat in the late stage of the energy release state.

[0052] In this embodiment, the third flexible gas storage tank has a design pressure of about 7-10 MPa, and stores compressed air for the expander to generate power; the first flexible gas storage tank has a first pressure of about 1-3 MPa, and the second flexible gas storage tank 202 has a second pressure of about 2-5 MPa. The first pressure gas is provided by the first external transmission pipeline 212 of the first flexible gas storage tank 201, and the first pressure gas can be used for industrial fluid transportation and the high-pressure side of large air-conditioning refrigeration units; the second pressure gas is provided by the second external transmission pipeline 213 of the second flexible gas storage tank 202, and the second pressure gas pressure is used for high-pressure fluid transportation, providing a high-pressure environment for chemical industry, and providing power for large machinery. At the same time, the gas temperature in the first flexible gas storage tank 201, the second flexible gas storage tank 202, and the third flexible gas storage tank 203 is at room temperature to reduce the difficulty of storing the flexible gas storage tanks.

[0053] The flexible air-regulating compressed air energy storage system provided by the present invention has the following advantages: (1) by setting the first flexible air storage tank 201 and the second flexible air storage tank 202, the outlet pressure of the compressor can be kept as constant as possible near the design point, that is, the compression efficiency of the compressor is always at a high efficiency, which has the advantage of high operating efficiency compared with the traditional compressor whose working condition changes due to the pressure change in the air storage tank; (2) the heat of the gas in the first air inlet pipeline 404, the second air inlet pipeline 405 and the third air inlet pipeline 406 is absorbed by the heat exchange component 3 respectively, By lowering the gas temperature, the compression efficiency of the second compressor 102 and the third compressor 103 is higher and the energy consumption is lower compared to the gas in a high temperature state; (3) the first flexible gas storage tank 201 can provide the third expander 403 with the first pressure gas in a continuous constant pressure state, the second flexible gas storage tank 202 can provide the second pressure gas in a continuous constant pressure state, and the third flexible gas storage tank 203 can provide the third pressure gas in a continuous constant pressure state to the third expander 403, so as to ensure that each expander is in rated working condition operation, which is extremely efficient. (4) in the energy release state, heat is provided to the gas in the first air inlet pipe 404 by delivering heat exchange medium to the fourth heat exchange branch pipe 326, heat is provided to the gas in the second air inlet pipe 405 by delivering heat exchange medium to the fifth heat exchange branch pipe 327, and heat is provided to the gas in the third air inlet pipe 406 by delivering heat exchange medium to the sixth heat exchange branch pipe 328, so as to ensure the heat requirement of the gas to drive the expander to do work; (5) the heat in the energy storage state is stored by the heat storage tank 307, and the heat is released in the energy release state, thereby avoiding heat waste and having a circular effect. (6) Gas is supplied to the first gas tank through the first gas transmission branch 206 and to the second gas tank through the second gas transmission branch 207, thereby ensuring the stability of the gas source of the first flexible gas tank 201 and the second flexible gas tank 202 when transmitting gas to the outside; (7) A first flow control valve 210, a second flow control valve 211, a third flow control valve, a fourth flow control valve and a connecting pipe 309 are provided to facilitate the connection of various heat exchange branches in the energy storage and energy release states, thereby reducing the overall number of valves, simplifying the pipeline structure, and ensuring heat exchange efficiency.

[0054] As an alternative embodiment, the number of compressors in the compressor assembly 1 may also be 2, 4, 5 or even more.

[0055] As an alternative embodiment, the number of expanders in the expansion assembly 4 can also be 2, 4, 5 or even more.

[0056] As an alternative embodiment, the heat exchange medium may also be other substances with heat conductive properties such as thermal oil and molten salt.

[0057] Although the embodiments of the present invention have been described with reference to the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention. Such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A flexible air-regulated compressed air energy storage system, characterized in that: include: A compressor assembly (1), the compressor assembly (1) comprising a first compressor (101), a second compressor (102), a first air outlet pipeline (104), and a second air outlet pipeline (105); the first compressor (101) and the second compressor (102) are arranged in series; the first air outlet pipeline (104) is provided between the air outlet end of the first compressor (101) and the air inlet end of the second compressor (102); and the second air outlet pipeline (105) is provided at the air outlet end of the second compressor (102); A flexible gas storage assembly (2) comprises a first air intake branch pipe (204), a first flexible air storage tank (201), a second air intake branch pipe (205), and a second flexible air storage tank (202); one end of the first air intake branch pipe (204) is connected to a first air outlet pipeline (104), and the other end of the first air intake branch pipe (204) is connected to the first flexible air storage tank (201); one end of the second air intake branch pipe (205) is connected to the second air outlet pipeline (105), and the other end of the second air intake branch pipe (205) is connected to the second flexible air storage tank (202).

2. The flexible gas-regulated compressed air energy storage system according to claim 1, characterized in that: The compressor assembly (1) further comprises a third compressor (103) and a third air outlet pipeline (106); the flexible air storage assembly (2) further comprises a third flexible air storage tank (203); a second air outlet pipeline (105) is provided between the second compressor (102) and the third compressor (103); and the third air outlet pipeline (106) is provided between the third compressor (103) and the third flexible air storage tank (203).

3. The flexible gas-regulated compressed air energy storage system according to any one of claims 1 to 2, characterized in that: The heat exchange assembly (3) further comprises a heat storage tank (307), a first heat exchanger (301), a second heat exchanger (302), a heat outlet main pipe (308), a heat inlet main pipe (310), a first heat exchange branch pipe (323), a second heat exchange branch pipe (324), a connecting pipe (309), a first heat inlet pipe (311) and a first heat outlet pipe (312), wherein the first heat exchange branch pipe (323) and the first air outlet pipe (104) are respectively arranged to pass through the first heat exchanger (301), and the second heat exchange branch pipe (324) and the second air outlet pipe (105) are respectively arranged to pass through the second heat exchanger ( 302) is provided, one end of the heat outlet main pipe (308) is connected to the heat storage tank (307), the other end of the heat outlet main pipe (308) is connected to the connecting pipe (309), the connecting pipe (309) is connected to the first heat inlet pipe (311), the two ends of the first heat exchange branch pipe (323) are respectively connected to the first heat inlet pipe (311) and the first heat outlet pipe (312), the two ends of the second heat exchange branch pipe (324) are respectively connected to the first heat inlet pipe (311) and the first heat outlet pipe (312), and the heat inlet main pipe (310) is respectively connected to the heat storage tank (307) and the first heat outlet pipe (312).

4. The flexible gas-regulated compressed air energy storage system according to claim 3, characterized in that: The heat exchange assembly (3) further comprises a third heat exchanger (303) and a third heat exchange branch pipe (325); the third heat exchange branch pipe (325) and the third outlet pipe (106) are respectively arranged to pass through the third heat exchanger (303); and the two ends of the third heat exchange branch pipe (325) are respectively connected to the first heat inlet pipe (311) and the first heat outlet pipe (312).

5. The flexible gas-regulated compressed air energy storage system according to claim 3, characterized in that: The invention also includes an expansion assembly (4), wherein the expansion assembly (4) includes a first expander (401), a second expander (402), a first air intake pipeline (404), and a second air intake pipeline (405); the first air intake pipeline (404) is provided between the first expander (401) and the third flexible air storage tank (203); and the second air intake pipeline (405) is provided between the first expander (401) and the second expander (402).

6. The flexible gas-regulated compressed air energy storage system according to claim 5, characterized in that: The flexible gas storage assembly (2) further comprises a first gas outlet branch pipe (208) and a first flow control valve (210); one end of the first gas outlet branch pipe (208) is in communication with the second flexible gas storage tank (202); the other end of the first gas outlet branch pipe (208) is in communication with the second gas inlet pipeline (405); and the first gas outlet branch pipe (208) is provided with a first flow control valve (210).

7. The flexible gas-regulated compressed air energy storage system according to claim 6, characterized in that: The flexible gas storage assembly (2) further comprises a second gas outlet branch pipe (209) and a second flow control valve (211); the expansion assembly (4) further comprises a third expander (403) and a third gas inlet pipeline (406); a third gas inlet pipeline (406) is provided between the second expander (402) and the third expander (403); one end of the second gas outlet branch pipe (209) is in communication with the first flexible gas storage tank (201); the other end of the second gas outlet branch pipe (209) is in communication with the third gas inlet pipeline (406); and a second flow control valve (211) is provided on the second gas outlet branch pipe (209).

8. The flexible gas-regulated compressed air energy storage system according to claim 7, characterized in that: The heat exchange assembly (3) further comprises a fourth heat exchanger (304), a fifth heat exchanger (305), a second heat inlet pipe (313), a second heat outlet pipe (314), a fourth heat exchange branch pipe (326) and a fifth heat exchange branch pipe (327), one end of the second heat inlet pipe (313) is in communication with the heat outlet main pipe (308), the other end of the second heat inlet pipe (313) is in communication with the connecting pipe (309), the fourth heat exchange branch pipe (326) and the first air inlet pipe (404) respectively pass through A fourth heat exchanger (304) is provided, and the fifth heat exchange branch pipe (327) and the second air inlet pipe (405) are respectively provided through the fifth heat exchanger (305), and the two ends of the fourth heat exchange branch pipe (326) are respectively connected to the second heat inlet pipe (313) and the second heat outlet pipe (314), and the two ends of the fifth heat exchange branch pipe (327) are respectively connected to the second heat inlet pipe (313) and the second heat outlet pipe (314), and the second heat outlet pipe (314) is connected to the connecting pipe (309).

9. The flexible gas-regulated compressed air energy storage system according to claim 8, characterized in that: The heat exchange assembly (3) further comprises a first connecting branch pipe (315), a second connecting branch pipe (317), a third connecting branch pipe (319), a fourth connecting branch pipe (321), a first heat exchange control valve (316), a second heat exchange control valve (318), a third heat exchange control valve (320) and a fourth heat exchange control valve (322); the first connecting branch pipe (315) is connected to the first heat inlet pipe (311) and the connecting pipe (309), the first connecting branch pipe (315) is provided with a first heat exchange control valve (316), the second connecting branch pipe (318) is provided with a first heat exchange control valve (319), and the fourth heat exchange control valve (322) is provided with a first heat exchange control valve (316). 17) are respectively connected to the first heat outlet pipe (312) and the connecting pipe (309); the second connecting branch pipe (317) is provided with a second heat exchange control valve (318); the third connecting branch pipe (319) is respectively connected to the second heat inlet pipe (313) and the connecting pipe (309); the third connecting branch pipe (319) is provided with a third heat exchange control valve (320); the fourth connecting branch pipe (321) is respectively connected to the second heat outlet pipe (314) and the connecting pipe (309); the fourth connecting branch pipe (321) is provided with a fourth heat exchange control valve (322).

10. A method for using a flexible gas-regulated compressed air energy storage system, for using the flexible gas-regulated compressed air energy storage system according to claim 1, characterized in that: In the energy storage state, the first compressor (101) generates first pressure gas which enters the first gas outlet pipeline (104); a portion of the first pressure gas in the first gas outlet pipeline (104) enters the second compressor (102), and another portion of the first pressure gas enters the first flexible gas storage tank (201) through the first gas inlet branch (204); the first pressure gas entering the second compressor (102) is compressed by the second compressor (102) and converted into second pressure gas which enters the second gas outlet pipeline (105); a portion of the second pressure gas in the second gas outlet pipeline (105) enters the second compressor (102), and another portion of the second pressure gas enters the second flexible gas storage tank (202) through the second gas inlet branch (205); and the first pressure value is less than the second pressure value.

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