Compressed air energy storage power station active cooling system and operation method

Abstract

The present invention discloses an active cooling system and operating method for a compressed air energy storage power station. The active cooling system for a compressed air energy storage power station includes a compressor unit, a turbine unit, a cooling circuit, a heat storage circuit, a first heat exchanger, and a second heat exchanger. The heat storage circuit includes a main circuit, a first branch circuit, and a second branch circuit. The first branch circuit and the second branch circuit are connected in parallel to each other and are respectively connected in series to the main circuit. A first circulation loop is formed between the first branch circuit and the main circuit, and a second circulation loop is formed between the second branch circuit and the main circuit. The second heat exchanger is arranged on the first branch circuit. The second heat exchanger is provided with a third heat exchange channel and a fourth heat exchange channel. The third heat exchange channel is connected to the first branch circuit, and the second heat exchange channel is connected to the cooling circuit. According to the active cooling system for a compressed air energy storage power station of the present invention, the circulation mode of the heat storage circuit can be adjusted according to the ambient temperature, thereby improving the adaptability and energy efficiency of the system and reducing operating costs.

Description

Technical Field

[0001] The present invention relates to the field of energy storage technology, and in particular to an active cooling system and an operating method for a compressed air energy storage power station. Background Art

[0002] The active cooling system of the compressed air energy storage power station stores energy through energy storage gas and releases gas to drive the turbine to generate electricity when needed, achieving efficient energy conversion and storage.

[0003] During the operation of a compressed air energy storage power station's active cooling system, the system must ensure that the compressed air is adequately cooled to meet the safe and efficient operation requirements of the subsequent turbine units. While ensuring the cooling of the compressed air, the cooling system must also fully release and effectively utilize excess thermal energy.

[0004] In the related art, since the excess heat energy is affected by the ambient temperature, it is difficult for the cooling system to accurately and effectively release the excess heat energy. Summary of the Invention

[0005] The present invention aims to address at least one of the technical problems existing in the prior art. To this end, one object of the present invention is to provide an active cooling system for a compressed air energy storage power station. This system can adjust the heat storage circuit's circulation mode based on ambient temperature, improving system adaptability and energy efficiency while reducing operating costs.

[0006] The present invention also proposes an operating method for the active cooling system of the compressed air energy storage power station.

[0007] The active cooling system of the compressed air energy storage power station according to the present invention comprises: a compressor unit and a turbine unit, wherein a gas flow channel is provided between the compressor unit and the turbine unit; a cooling circuit, wherein a circulating cooling medium is provided in the cooling circuit, and wherein the cooling circuit is connected to the compressor unit and the turbine unit; a heat storage circuit, wherein a circulating heat storage medium is provided in the heat storage circuit, and wherein the heat storage circuit comprises a main circuit, a first branch circuit and a second branch circuit, wherein the first branch circuit and the second branch circuit are connected in parallel to each other and are respectively connected in series to the main circuit, and a heat storage circuit is formed between the first branch circuit and the main circuit. A first circulation loop is formed, and a second circulation loop is formed between the second branch and the main line; a first heat exchanger, the first heat exchanger is arranged on the main line, the first heat exchanger is provided with a first heat exchange channel and a second heat exchange channel, the first heat exchange channel is connected to the main line, and the second heat exchange channel is connected to the gas channel; a second heat exchanger, the second heat exchanger is arranged on the first branch, the second heat exchanger is provided with a third heat exchange channel and a fourth heat exchange channel, the third heat exchange channel is connected to the first branch, and the second heat exchange channel is connected to the cooling circuit.

[0008] According to the present invention, the active cooling system for a compressed air energy storage power station forms a first circulation loop between the first branch and the main circuit, and a second circulation loop between the second branch and the main circuit. This allows for flexible selection of circulation modes for the heat storage circuit based on different operating conditions and requirements. By installing a second heat exchanger on the first branch, the heat storage medium in the heat storage circuit can effectively exchange heat with the cooling medium when the first circulation loop is activated, lowering the temperature of the heat storage medium in the heat storage circuit to ensure that the heat storage medium can effectively absorb the heat of the energy storage gas during the charging phase. Depending on the impact of ambient temperature on excess heat energy, the first or second circulation loop can be flexibly activated. Specifically, when the ambient temperature is high, the system is more likely to accumulate excess heat energy, causing the heat storage medium temperature to rise. In this case, activating the first circulation loop and using the cooling medium via the second heat exchanger to cool the heat storage medium effectively lowers its temperature, preparing for the subsequent charging phase. When the ambient temperature is low, the system accumulates relatively little excess heat energy, maintaining a low temperature for the heat storage medium. At this point, the second circulation loop is activated, eliminating the need for additional cooling by the cooling medium and meeting the needs of the charging phase, resulting in lower costs. Therefore, the active cooling system of the compressed air energy storage power station can better adapt to various complex operating conditions, reducing energy consumption and operating costs.

[0009] According to some embodiments of the present invention, the active cooling system of the compressed air energy storage power station further includes: a high-temperature heat storage tank and a low-temperature heat storage tank, the heat storage tank and the low-temperature heat storage tank are respectively used to store heat storage medium, and the high-temperature heat storage tank and the low-temperature heat storage tank are arranged in series on the trunk line; wherein the trunk line includes a first trunk line and a second trunk line, the first trunk line is located between the downstream of the high-temperature heat storage tank and the upstream of the low-temperature heat storage tank, the second trunk line is located between the upstream of the high-temperature heat storage tank and the downstream of the low-temperature heat storage tank, the first branch line and the second branch line are arranged in parallel on the second trunk line; the first heat exchanger is configured as a plurality of, at least one of the first heat exchangers is arranged The first main line and at least another first heat exchanger are arranged in the second main line and are located downstream of the first branch and the second branch. The heat storage circuit further includes: a third branch, one end of the third branch is connected to the low-temperature heat storage tank, and the other end of the third branch is connected to the second main line between the first branch and the first heat exchanger. The first circulation circuit includes a first circuit and a second circuit. The first circuit is formed by the high-temperature heat storage tank, the first main line, the low-temperature heat storage tank, the first branch, and the second main line. The second circuit is formed by the low-temperature heat storage tank, the first branch, the third branch, and a portion of the second main line.

[0010] According to some embodiments of the present invention, the heat storage circuit further includes: a fourth branch, one end of the fourth branch being connected to the first trunk line between the high-temperature heat storage tank and the first heat exchanger, and the other end of the fourth branch being connected to the first branch upstream of the second heat exchanger.

[0011] According to some embodiments of the present invention, the cooling circuit is provided with a main cooling pump and a secondary cooling pump connected in parallel with each other.

[0012] The following describes an operating method of the active cooling system for a compressed air energy storage power station according to any one of the above embodiments of the present invention.

[0013] The operating method according to the present invention is used for the active cooling system of a compressed air energy storage power station in any of the above-mentioned embodiments. The operating method includes: determining the operating condition of the active cooling system of the compressed air energy storage power station and obtaining the actual cooling load after the low-pressure gas storage condition begins, and calculating the expected cooling load before the charging condition begins based on the actual cooling load and the weather temperature forecast value; and determining and selecting the circulation mode of the heat storage circuit based on the difference between the expected cooling load and the rated design condition cooling load.

[0014] According to some embodiments of the present invention, the active cooling system of the compressed air energy storage power station includes: a high-temperature heat storage tank and a low-temperature heat storage tank, the heat storage tank and the low-temperature heat storage tank are respectively used to store heat storage medium, the high-temperature heat storage tank and the low-temperature heat storage tank are arranged in series on the trunk line, the trunk line includes a first trunk line and a second trunk line, the first trunk line is located between the downstream of the high-temperature heat storage tank and the upstream of the low-temperature heat storage tank, the second trunk line is located between the upstream of the high-temperature heat storage tank and the downstream of the low-temperature heat storage tank, the first branch line and the second branch line are arranged in parallel on the second trunk line; the first heat exchanger is configured as a plurality of, at least one of the first heat exchangers The heat storage circuit further comprises a first circuit and a second circuit. The first circuit comprises a heat exchanger disposed on the first trunk line and downstream of the first branch line and the second branch line. The heat storage circuit further comprises a third branch line, one end of the third branch line being connected to the low-temperature heat storage tank, and the other end of the third branch line being connected to the second trunk line between the first branch line and the first heat exchanger. The first circulation circuit comprises a first circuit and a second circuit. The first circuit is formed by the high-temperature heat storage tank, the first trunk line, the low-temperature heat storage tank, the first branch line, and the second trunk line. The second circuit is formed by the low-temperature heat storage tank, the first branch line, and the third branch line.

[0015] Determining and selecting the circulation mode of the heat storage cycle based on the difference between the expected cooling load and the rated design operating condition cooling load includes: determining that the difference between the expected cooling load and the rated design operating condition cooling load is less than or equal to a first set difference, and starting the second circulation loop; or, determining that the difference between the expected cooling load and the rated design operating condition cooling load is greater than the first set difference and less than or equal to the second set difference, and starting the first loop; or, determining that the difference between the expected cooling load and the rated design operating condition cooling load is greater than the second set difference, and starting the second loop.

[0016] According to some embodiments of the present invention, the operating method further includes: before the charging condition begins, obtaining the actual cooling load, determining whether the actual cooling load has dropped to the rated design condition cooling load, and determining to start the first loop, the second loop, or the second circulation loop based on the determination result.

[0017] According to some embodiments of the present invention, determining whether to start the first loop, the second loop, or the second circulation loop based on the determination result includes: if the determination result is yes, starting the second circulation loop; if the determination result is no, starting the second loop and determining whether to start the first loop based on the current electricity price.

[0018] According to some embodiments of the present invention, a high-temperature heat storage tank and a low-temperature heat storage tank are provided on the heat storage circuit; and the operating method further comprises: after the low-pressure gas storage condition begins, obtaining a liquid level of the high-temperature heat storage tank, and determining, based on the liquid level of the high-temperature heat storage tank, whether it is necessary to cool the heat storage medium in the high-temperature heat storage tank and transfer it to the low-temperature heat storage tank.

[0019] According to some embodiments of the present invention, the operating method further includes: selecting the start and end times of the energy release condition, the low-pressure gas storage condition, the energy charging condition and the high-pressure gas storage condition according to the daily electricity price distribution.

[0020] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments with reference to the accompanying drawings, in which:

[0022] Figure 1 2 is a schematic structural diagram of an active cooling system for a compressed air energy storage power station according to an embodiment of the present invention;

[0023] Figure 2 is a flow chart of an operating method of an active cooling system for a compressed air energy storage power station according to one embodiment of the present invention;

[0024] Figure 3 is a flow chart of an operating method of an active cooling system for a compressed air energy storage power station according to another embodiment of the present invention;

[0025] Figure 4 is a flow chart of an operating method of an active cooling system for a compressed air energy storage power station according to one embodiment of the present invention;

[0026] Figure 5 2. It is a schematic diagram of a temperature curve of a liquid storage medium in a low-temperature heat storage tank of an active cooling system of a compressed air energy storage power station according to one embodiment of the present invention;

[0027] Figure 6 1 is a schematic diagram of the cooling load timing of the active cooling system of a compressed air energy storage power station under rated operating conditions according to one embodiment of the present invention.

[0028] Reference numerals:

[0029] 1. Active cooling system of compressed air energy storage power station;

[0030] 111. Compressor unit, 112. Turbine unit, 113. Gas flow channel;

[0031] 12. Cooling circuit, 121. Main cooling pump, 122. Auxiliary cooling pump, 123. Cooling source;

[0032] 13. Heat storage circuit, 131. Main circuit, 1311. First main circuit, 1312. Second main circuit, 132. First branch circuit, 133. Second branch circuit, 134. Third branch circuit, 135. Fourth branch circuit, 136. High-temperature pump, 137. Low-temperature pump;

[0033] 14. First heat exchanger, 15. Second heat exchanger, 16. High-temperature heat storage tank, 17. Low-temperature heat storage tank, 18. Gas storage. DETAILED DESCRIPTION

[0034] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention.

[0035] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, features defined as "first" or "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0036] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0037] In the related art, since the excess heat energy is affected by the ambient temperature, it is difficult for the cooling system to accurately and effectively release the excess heat energy.

[0038] Reference below Figures 1-6 The active cooling system 1 of a compressed air energy storage power station according to an embodiment of the present invention is described.

[0039] like Figure 1 As shown, the active cooling system 1 of the compressed air energy storage power station according to the present invention includes a compressor unit 111 and a turbine unit 112. The compressor unit 111 is responsible for compressing the gas to reduce its volume, increase its pressure, and increase its temperature, thereby storing energy. When the stored energy needs to be released, the high-pressure gas is released and enters the turbine unit 112. In the turbine unit 112, the high-pressure gas expands and performs work, thereby converting the pressure energy of the gas into mechanical energy and then into electrical energy. A gas flow channel 113 is provided between the compressor unit 111 and the turbine unit 112, so that the compressed high-pressure gas can be smoothly and efficiently transferred to the turbine unit 112 for subsequent expansion work and power generation processes.

[0040] The active cooling system 1 for the compressed air energy storage power station also includes a cooling circuit 12, which contains a circulating cooling medium. This circulating cooling medium absorbs and removes heat, achieving heat dissipation and temperature reduction. Cooling circuit 12 is connected to the compressor unit 111 and turbine unit 112. Therefore, when the compressor unit 111 and turbine unit 112 generate heat during operation, the cooling medium can promptly absorb the heat and remove it through circulation, thereby ensuring the normal operation and overall stability of the system.

[0041] The active cooling system 1 for a compressed air energy storage power station also includes a heat storage circuit 13, which contains a circulating heat storage medium. The circulation of the heat storage medium effectively absorbs, stores, and releases thermal energy. During the charging phase, the flow of the heat storage medium absorbs heat from the stored gas, cooling it and enabling it to be stored in a more stable and secure state. During the discharge phase, the flow of the heat storage medium releases heat to heat the stored gas, thereby increasing its temperature and pressure and providing sufficient energy for subsequent power generation by the turbine unit 112.

[0042] The heat storage circuit 13 includes a main circuit 131, a first branch 132, and a second branch 133. The first branch 132 and the second branch 133 are connected in parallel to each other and are respectively connected in series to the main circuit 131. A first circulation loop is formed between the first branch 132 and the main circuit 131, and a second circulation loop is formed between the second branch 133 and the main circuit 131. This allows the heat storage circuit 13 to flexibly select a circulation mode according to different working conditions and needs.

[0043] The active cooling system 1 for a compressed air energy storage power station also includes a first heat exchanger 14 and a second heat exchanger 15. The first heat exchanger 14 is disposed on a main line 131 and is provided with a first heat exchange channel and a second heat exchange channel. The first heat exchange channel communicates with the main line 131, and the second heat exchange channel communicates with the gas channel 113. Therefore, the first heat exchanger 14 is used to achieve heat exchange between the heat storage medium and the energy storage gas. The second heat exchanger 15 is disposed on a first branch line 132 and is provided with a third heat exchange channel and a fourth heat exchange channel. The third heat exchange channel communicates with the first branch line 132, and the second heat exchange channel communicates with the cooling circuit 12. Therefore, the second heat exchanger 15 is used to achieve heat exchange between the heat storage medium and the cooling medium.

[0044] By providing the second heat exchanger 15 on the first branch 132, the heat storage medium in the heat storage circuit 13 can effectively exchange heat with the cooling medium when the circulation mode of the first circulation circuit is started, thereby reducing the temperature of the heat storage medium in the heat storage circuit 13 to ensure that the heat storage medium can effectively absorb the heat of the energy storage gas during the charging stage.

[0045] Depending on the impact of the ambient temperature on the surplus thermal energy, you can flexibly choose to start the first circulation loop or the second circulation loop. Specifically, when the ambient temperature is high, the system is more likely to accumulate surplus thermal energy, causing the temperature of the heat storage medium to rise. At this time, starting the first circulation loop and using the cooling medium to cool the heat storage medium through the second heat exchanger 15 can effectively reduce its temperature and prepare for the next charging stage. When the ambient temperature is low, the surplus thermal energy accumulated by the system is relatively small, and the temperature of the heat storage medium is maintained at a low level. At this time, starting the second circulation loop can meet the needs of the charging stage without relying on the cooling medium for additional cooling, and the cost is lower. Therefore, the active cooling system 1 of the compressed air energy storage power station can better adapt to various complex working conditions and reduce energy consumption and operating costs.

[0046] Therefore, according to the active cooling system 1 of the compressed air energy storage power station of the present invention, the circulation mode of the heat storage loop 13 can be adjusted according to the ambient temperature, thereby improving the system adaptability and energy efficiency and reducing operating costs.

[0047] According to some embodiments of the present invention, Figure 1 As shown, the active cooling system 1 of the compressed air energy storage power station also includes a gas storage reservoir 18, which is arranged on the gas flow channel 113. The gas storage reservoir 18 is used to store compressed gas. During the charging stage, the gas is compressed by the compressor unit 111. The compressed gas has a high pressure and energy density, which is suitable for subsequent energy storage and power generation processes. The compressed gas is transported to the gas storage reservoir 18 for storage so that the stored energy can be quickly released and utilized when needed. During the energy release stage, the high-pressure gas in the gas storage reservoir 18 is released and transported to the turbine unit 112 to meet the power generation needs.

[0048] According to some embodiments of the present invention, Figure 1 As shown, the active cooling system 1 of the compressed air energy storage power station also includes a high-temperature heat storage tank 16 and a low-temperature heat storage tank 17. The heat storage tank and the low-temperature heat storage tank 17 are respectively used to store heat storage media. The high-temperature heat storage tank 16 and the low-temperature heat storage tank 17 are arranged in series on the trunk line 131. Specifically, the high-temperature heat storage tank 16 is used to store the heat storage medium with a high temperature that has absorbed a large amount of heat from the energy storage gas during the charging stage. The high-temperature heat storage medium can be released when needed to provide energy for heating the energy storage gas or other heat energy utilization equipment. The low-temperature heat storage tank 17 is used to store the heat storage medium whose temperature has dropped after the energy release stage or has been cooled. At the beginning of the next round of charging stage, the low-temperature heat storage medium can be reheated and used to absorb the heat of new energy storage gas.

[0049] The main circuit 131 includes a first main circuit 1311 and a second main circuit 1312. The first main circuit 1311 is located between the downstream of the high-temperature heat storage tank 16 and the upstream of the low-temperature heat storage tank 17. Therefore, the first main circuit 1311 is used to transfer the heat storage medium in the high-temperature heat storage tank 16 to the low-temperature heat storage tank 17. The second main circuit 1312 is located between the upstream of the high-temperature heat storage tank 16 and the downstream of the low-temperature heat storage tank 17. Therefore, the second main circuit 1312 is used to transfer the heat storage medium in the low-temperature heat storage tank 17 to the high-temperature heat storage tank 16. The first branch circuit 132 and the second branch circuit 133 are arranged in parallel with the second main circuit 1312. Therefore, during the process of transferring the heat storage medium from the low-temperature heat storage tank 17 to the high-temperature heat storage tank 16, the second heat exchanger 15 on the first branch circuit 132 can further reduce the temperature of the heat storage medium, allowing the heat storage medium to more efficiently absorb the thermal energy of the energy storage gas during the charging phase.

[0050] Multiple first heat exchangers 14 are provided, with at least one first heat exchanger 14 disposed on the first main line 1311 and at least another first heat exchanger 14 disposed on the second main line 1312, downstream of the first branch line 132 and the second branch line 133. During the transfer of the heat storage medium from the high-temperature heat storage tank 16 to the low-temperature heat storage tank 17 via the first main line 1311, the heat storage medium can exchange heat with the stored energy gas through the first heat exchanger 14, raising the temperature of the stored energy gas and enabling the stored energy gas to more efficiently drive the turbine to generate electricity. During the transfer of the heat storage medium from the low-temperature heat storage tank 17 to the high-temperature heat storage tank 16 via the second main line 1312, the heat storage medium can exchange heat with the stored energy gas through the first heat exchanger 14, lowering the temperature of the stored energy gas and enabling the compressed stored energy gas to be stored in a more stable and secure state.

[0051] The heat storage circuit 13 also includes a third branch 134, one end of which is connected to the low-temperature heat storage tank 17, and the other end of the third branch 134 is connected to the second trunk 1312 between the first branch 132 and the first heat exchanger 14, so that the heat storage medium flowing out of the first branch 132 can directly return to the low-temperature heat storage tank 17 through the third branch 134, shortening the flow path of the heat storage medium and improving the heat dissipation efficiency.

[0052] The first circulation loop consists of a first loop and a second loop. The first loop is formed by the high-temperature heat storage tank 16, the first main line 1311, the low-temperature heat storage tank 17, the first branch 132, and the second main line 1312. The second loop is formed by the low-temperature heat storage tank 17, the first branch 132, the third branch 134, and a portion of the second main line 1312. This allows the heat storage loop 13 to flexibly select a circulation method based on different operating conditions and requirements. When the first loop is selected, the heat storage medium circulates between the high-temperature heat storage tank 16 and the low-temperature heat storage tank 17 and is cooled by the second heat exchanger 15 on the first branch 132. When the second loop is selected, the heat storage medium flows from the low-temperature heat storage tank 17 and is cooled by the second heat exchanger 15 on the first branch 132. After flowing out of the first branch 132, it returns to the low-temperature heat storage tank 17 through the third branch 134, achieving higher cooling efficiency. When the first loop is activated, the appropriate circulation method can be determined and selected based on the cooling load, electricity price, and the need to optimize system energy efficiency.

[0053] According to some embodiments of the present invention, Figure 1 As shown, a high-temperature pump 136 is provided on the first main line 1311, which is used to drive the heat storage medium from the high-temperature heat storage tank 16 to the low-temperature heat storage tank 17. A low-temperature pump 137 is provided on the second main line 1312 and is located between the low-temperature heat storage tank 17 and the first branch line 132 (or the second branch line 133). The low-temperature pump 137 is used to drive the heat storage medium from the low-temperature heat storage tank 17 to the first branch line 132 (or the second branch line 133). By providing high-temperature pump 136 and low-temperature pump 137, when the first circuit, the second circuit, or the second circulation circuit is activated, at least one of the low-temperature pump 137 and high-temperature pump 136 is used to provide the power to drive the flow of the heat storage medium, thereby ensuring the circulation of the heat storage medium.

[0054] According to some embodiments of the present invention, Figure 1As shown, the heat storage circuit 13 also includes a fourth branch 135. One end of the fourth branch 135 is connected to the first main circuit 1311 between the high-temperature heat storage tank 16 and the first heat exchanger 14, and the other end of the fourth branch 135 is connected to the first branch 132 upstream of the second heat exchanger 15. By providing this fourth branch 135, the remaining heat storage medium in the high-temperature heat storage tank 1616 can be transferred after the turbine ends, ensuring a sufficient amount of heat storage medium for the next cycle of the system. During this transfer process, the heat storage medium not only flows through the fourth branch 135 to the first branch 132, where it is then cooled by the second heat exchanger 15 on the first branch 132 and the cooling circuit 12, but this transfer process also takes into account the cooling efficiency range of the cooling system to ensure effective cooling. Simultaneously, the heat energy in the high-temperature heat storage tank 16 is effectively reduced and released during this transfer process. The heat storage medium flowing out of the first branch 132 can directly flow into the low-temperature heat storage tank 17 through the third branch 134 , thereby effectively cooling the high-temperature heat storage medium in the high-temperature heat storage tank 16 and smoothly introducing it into the low-temperature heat storage tank 17 .

[0055] It's worth noting that excess heat energy is primarily generated during the system's energy release phase. To ensure the stability of the turbine unit 112's inlet air temperature, the temperature of the low-temperature heat storage tank 17 often rises above its design value during actual operation. This phenomenon is primarily due to the fact that, during the energy release process, to maintain stable turbine operation, the first heat exchanger 14 operates in two control modes: output air temperature control mode and output heat medium water temperature control mode. The timing of switching between these two modes is closely tied to the system's operational stability. Particularly during the energy release phase under summer operating conditions, when the first heat exchanger 14 adopts the air temperature control mode, the temperature of the low-temperature heat storage medium rises above its design value, which in turn causes the average temperature of the low-temperature heat storage tank 17 to rise accordingly. Therefore, to maintain stable operation of the turbine unit 112, the temperature of the low-temperature heat storage tank 17 is often observed to be above its design value.

[0056] According to some embodiments of the present invention, Figure 1 As shown, the cooling circuit 12 is provided with a main cooling pump 121 and a secondary cooling pump 122, which are arranged in parallel with each other. The main cooling pump 121 and the secondary cooling pump 122 are parallel in the cooling circuit 12, and each independently draws cooling medium from a cooling source 123 (such as a cooling tower) and delivers the cooling medium to the equipment or system requiring cooling. Because the main cooling pump 121 and the secondary cooling pump 122 are connected in parallel, the operations of the main cooling pump 121 and the secondary cooling pump 122 do not interfere with each other, and they can operate independently as needed.

[0057] During the charging phase, the cooling load of the compressed air energy storage power station's active cooling system 1 is high. At this time, the primary cooling pump 121 is activated to meet the system's high demand for cooling medium. During the remaining phases, the cooling load of the compressed air energy storage power station's active cooling system 1 is relatively low. During these times, the system still requires a certain amount of cooling capacity, and the secondary cooling pump 122 is activated to provide the necessary cooling medium flow and pressure.

[0058] Reference below Figure 2-Figure 6 The operating method of the active cooling system 1 for a compressed air energy storage power station according to any one of the above embodiments of the present invention is described.

[0059] like Figure 2 、 Figure 4 and Figure 5 As shown, the operating method according to the present invention is used for the active cooling system 1 of the compressed air energy storage power station in any of the above-mentioned embodiments. The operating method includes: judging the operating condition of the active cooling system 1 of the compressed air energy storage power station and obtaining the actual cooling load after the low-pressure gas storage condition starts, and calculating the expected cooling load before the charging condition starts based on the actual cooling load and the weather temperature forecast value; judging and selecting the circulation mode of the heat storage circuit 13 based on the difference between the expected cooling load and the rated design condition cooling load.

[0060] According to the operating method of the present invention, the operating method will first determine the current operating condition of the active cooling system 1 of the compressed air energy storage power station. The active cooling system 1 of the compressed air energy storage power station has an energy release condition, a low-pressure gas storage condition, a charging condition and a high-pressure gas storage condition. The energy release condition refers to the stage in which the high-pressure energy storage gas is released and expands and performs work through the turbine unit 112, thereby generating electrical energy. The low-pressure gas storage condition refers to the stage in which the pressure of the energy storage gas is reduced and stored after the energy storage gas expands and performs work through the turbine unit 112. The charging condition refers to the stage in which the compressor unit 111 operates to compress the energy storage gas and store it in the gas storage reservoir 18. The high-pressure gas storage condition refers to the stage in which the pressure of the energy storage gas in the gas storage reservoir 18 reaches a peak value, which occurs after the charging stage.

[0061] By determining the current operating condition of the active cooling system 1 of the compressed air energy storage power station, a corresponding cooling strategy can be implemented according to the cooling requirements of each operating condition.

[0062] After the low-pressure gas storage condition begins, the operation method will obtain the actual cooling load at this time. The actual cooling load reflects the current heat dissipation demand of the system. Next, the operation method will calculate the expected cooling load before the charging condition begins based on the actual cooling load and the weather temperature forecast value. The weather temperature will affect the cooling demand of the system. The weather temperature forecast value can be used to more accurately estimate the future cooling load. Finally, the operation method will determine and select the circulation mode of the heat storage circuit 13 based on the difference between the expected cooling load and the rated design condition cooling load. The rated design condition cooling load is the maximum cooling load considered when the system is designed. If the expected cooling load exceeds this value, the operation method will select a more efficient circulation mode by adjusting the flow path of the heat storage medium. If the expected cooling load is low, a more energy-saving circulation mode can be selected.

[0063] For example, the circulation mode of the heat storage circuit 13 is determined by judging the water temperature of the low-temperature water tank and calculating the temperature drop curve of the low-temperature heat storage tank 17. Specifically, the temperature drop curve of the low-temperature heat storage tank 17 is calculated according to the natural convection formula (Formula 1). Where T is the low-temperature water temperature in the storage tank (unit: K), Ta is the ambient temperature variable (unit: K), T0 is the starting temperature of the low-temperature water in the storage tank (unit: K), and h is the heat transfer coefficient under natural convection conditions of the storage tank (unit: W / (m 2 ·K), A is the surface area of ​​heat exchange between the tank and the atmosphere (unit: m 2 ), m is the mass of low-temperature water in the storage tank (unit: kg), and c is the specific heat capacity of low-temperature water (unit: J / (kg·K)).

[0064]

[0065] According to some embodiments of the present invention, the active cooling system 1 of the compressed air energy storage power station includes: a high-temperature heat storage tank 16 and a low-temperature heat storage tank 17, the heat storage tank and the low-temperature heat storage tank 17 are respectively used to store heat storage medium, the high-temperature heat storage tank 16 and the low-temperature heat storage tank 17 are arranged in series on a trunk 131, the trunk 131 includes a first trunk 1311 and a second trunk 1312, the first trunk 1311 is located between the downstream of the high-temperature heat storage tank 16 and the upstream of the low-temperature heat storage tank 17, the second trunk 1312 is located between the upstream of the high-temperature heat storage tank 16 and the downstream of the low-temperature heat storage tank 17, the first branch 132 and the second branch 133 are arranged in parallel on the second trunk 1312; the first heat exchanger 14 is constructed in multiple ways, at least one first heat exchanger 14 is arranged in the first trunk 1311, and at least another first heat exchanger 14 is arranged in the second trunk 1312 and is located downstream of the first branch 132 and the second branch 133; the heat storage circuit 13 also includes: a third branch 134, one end of the third branch 134 is connected to the low-temperature heat storage tank 17, and the other end of the third branch 134 is connected to the second trunk 1312 between the first branch 132 and the first heat exchanger 14. The first circulation circuit includes a first circuit and a second circuit. The first circuit is formed by the high-temperature heat storage tank 16, the first trunk 1311, the low-temperature heat storage tank 17, the first branch 132, and the second trunk 1312, and the second circuit is formed by the low-temperature heat storage tank 17, the first branch 132, and the third branch 134.

[0066] like Figure 2 、 Figure 4 and Figure 5 As shown, determining and selecting a circulation mode of the heat storage cycle based on the difference between the expected cooling load and the rated design operating condition cooling load includes: determining that the difference between the expected cooling load and the rated design operating condition cooling load is less than or equal to a first set difference, and starting the second circulation loop; or determining that the difference between the expected cooling load and the rated design operating condition cooling load is greater than the first set difference and less than or equal to the second set difference, and starting the first loop; or determining that the difference between the expected cooling load and the rated design operating condition cooling load is greater than the second set difference, and starting the second loop.

[0067] When the difference between the expected cooling load and the rated design cooling load is less than or equal to a first set difference, the second circulation loop is activated. When cooling demand is relatively low, cooling through the second circulation loop allows for more efficient use of thermal energy while reducing unnecessary energy consumption. At this point, the heat storage medium circulates between the high-temperature heat storage tank 16 and the low-temperature heat storage tank 17 to provide appropriate cooling, meeting cooling demand while avoiding energy waste.

[0068] When the difference between the expected cooling load and the rated design cooling load is greater than a first set difference but less than or equal to a second set difference, the system activates the first circuit. When the cooling demand is moderate, the thermal storage medium continues to circulate between the high-temperature thermal storage tank 16 and the low-temperature thermal storage tank 17. However, due to the increased cooling demand, the thermal storage medium passes through the second heat exchanger 15 on the first branch 132 to further reduce its temperature. The first circuit provides more sufficient cooling capacity to ensure system temperature stability.

[0069] When the difference between the expected cooling load and the rated design cooling load exceeds a second set difference, the system activates the second circuit. When the system accumulates a large amount of excess heat energy, the second circuit achieves higher cooling efficiency, performing deep cooling via the second heat exchanger 15 on the first branch 132. The cooled heat storage medium is then returned directly to the low-temperature heat storage tank 17 via the third branch 134, ensuring the system is fully prepared for the next charging phase. Despite relatively high energy consumption, the system achieves stable operation and optimized energy efficiency under extreme operating conditions.

[0070] Therefore, by flexibly selecting the heat storage cycle method based on the difference between the expected cooling load and the rated design operating cooling load, the system can efficiently utilize thermal energy and reduce energy consumption when the cooling demand is low, provide sufficient cooling to ensure temperature stability when the cooling demand is moderate, and achieve deep cooling to ensure stable system operation when the cooling demand is high, thereby optimizing energy efficiency, reducing costs, and adapting to various complex operating conditions.

[0071] For example, when the difference ΔT between the temperature of the low-temperature heat storage tank 17 at the beginning of the charging phase and the low-temperature water design temperature set during the charging phase satisfies the condition of ΔT≤5%, the second circulation loop will be activated to achieve more energy-saving and efficient thermal energy management. When ΔT exceeds 5% but does not exceed 7%, that is, 5%<ΔT≤7%, the system will choose to activate the first loop to ensure that the heat storage medium can be fully cooled, thereby maintaining the stability of the system temperature. If ΔT increases further and exceeds 7%, the system will activate the second loop, but at this time adopt a more efficient cooling mode to cope with the situation where the system accumulates a lot of surplus heat energy, ensuring that the system can be fully prepared before the charging phase to achieve stable operation and energy efficiency optimization.

[0072] In the described embodiment, the thresholds of 5% and 7% are determined based on a comprehensive consideration of the designed low-temperature heat storage medium temperature of the low-temperature heat storage tank 17, the designed heat exchange capacity of the heat exchanger, and the reserved heat exchange margin. These parameters are selected to optimize the thermal management process, ensuring that the system can adopt the most energy-efficient and efficient operating strategy under varying temperature differentials (ΔT). This includes selectively activating the first and second circuits and adjusting the cooling mode to maintain system temperature stability, effectively manage and dissipate accumulated excess heat energy, and ensure adequate system preparation before the charging phase, ultimately achieving stable operation and optimized energy efficiency.

[0073] According to some embodiments of the present invention, Figure 2 、 Figure 4 and Figure 5 As shown, the operating method also includes: before the charging condition starts, obtaining the actual cooling load, determining whether the actual cooling load drops to the rated design condition cooling load, and determining to start the first circuit, the second circuit or the second circulation circuit based on the determination result.

[0074] Before charging—that is, before compressing the energy storage gas and storing energy—the current actual cooling load is obtained. This actual cooling load reflects the cooling capacity actually required to maintain normal operation under the current system conditions. Next, by determining whether the actual cooling load has fallen below the rated design cooling load, it can be determined whether the design cooling effect has been achieved. Based on this determination, the most appropriate heat storage cycle method is selected for activation.

[0075] If the system's cooling demand has decreased, the second loop can be activated to maintain stable system operation in a more energy-efficient and efficient manner. If the actual cooling load is still higher than the rated design cooling load, it indicates that the system still needs more cooling capacity to meet current operating needs, so either the first or second loop can be activated. Both the first and second loops offer higher cooling efficiency, enabling them to quickly and effectively dissipate excess heat from the thermal storage system, ensuring energy balance for the next storage cycle.

[0076] According to some embodiments of the present invention, Figure 2 and Figure 4 As shown, determining whether to start the first circuit, the second circuit or the second circulation circuit according to the determination result includes: if the determination result is yes, starting the second circulation circuit; if the determination result is no, starting the second circuit and determining whether to start the first circuit according to the current electricity price.

[0077] If the judgment result is yes, that is, the predicted cooling load has dropped to the rated design operating cooling load, indicating that the system has achieved the cooling effect under the design state, the second circulation loop will be started at this time, because the second circulation loop can maintain the stable operation of the system while operating in a more energy-saving and efficient manner, thereby further reducing the system's energy consumption and operating costs.

[0078] If the judgment result is no, that is, the predicted cooling load is still higher than the rated design operating condition cooling load, the system needs more cooling capacity to meet the current operating needs, and the second circuit is started to provide more sufficient cooling capacity. And the current electricity price is used to choose whether to start the first circuit to achieve optimal energy efficiency and economy. Specifically, the daily electricity price will fluctuate at different times, with higher prices during peak electricity consumption periods and lower prices during off-peak electricity consumption periods. If the electricity price happens to be at a peak time, you can choose to start the first circuit. Considering that the electricity price is higher during peak hours, starting the first circuit with relatively low energy consumption can help reduce electricity expenses, thereby reducing overall operating costs. On the contrary, if the current electricity price is at a low point, you can choose not to start the first circuit and keep the second circuit started, so that you can use the off-peak period for efficient cooling operations and provide a more efficient cooling effect for the charging phase.

[0079] According to some embodiments of the present invention, Figure 2 As shown, the heat storage circuit 13 is provided with a high-temperature heat storage tank 16 and a low-temperature heat storage tank 17; the operating method further includes: after the low-pressure gas storage condition begins, obtaining the liquid level of the high-temperature heat storage tank 16, and determining whether the heat storage medium in the high-temperature heat storage tank 16 needs to be cooled and transported to the low-temperature heat storage tank 17 based on the liquid level of the high-temperature heat storage tank 16.

[0080] After the low-pressure gas storage condition begins, the liquid level information of the heat storage medium in the high-temperature heat storage tank 16 is first obtained. The liquid level information reflects the amount of heat storage medium in the heat storage tank. By monitoring the liquid level, it can be determined whether the liquid level of the heat storage medium in the high-temperature heat storage tank 16 has reached the designed low liquid level. If the liquid level is lower than the designed low liquid level, it indicates that the amount of heat storage medium in the low-temperature heat storage tank 17 is sufficient to meet the low-temperature heat storage medium demand of the charging condition. Therefore, there is no need to cool the heat storage medium in the high-temperature heat storage tank 16 and transfer it to the low-temperature heat storage tank 17. If the liquid level is higher than the designed low liquid level, it indicates that the amount of heat storage medium in the low-temperature heat storage tank 17 is insufficient to meet the low-temperature heat storage medium demand of the charging condition. Therefore, it is necessary to cool the heat storage medium in the high-temperature heat storage tank 16 and transfer it to the low-temperature heat storage tank 17.

[0081] For example, the heat storage medium flowing out of the high-temperature heat storage tank 16 can flow to the first branch 132 through the fourth branch 135, and then exchange heat with the cooling circuit 12 through the second heat exchanger 15 on the first branch 132 for cooling. The heat storage medium flowing out of the first branch 132 can directly flow into the low-temperature liquid outlet tank through the third branch 134, thereby cooling the high-temperature heat storage medium in the high-temperature heat storage tank 16 and introducing it into the low-temperature heat storage tank 17.

[0082] According to some embodiments of the present invention, Figure 3 and Figure 6 As shown, the operating method also includes: selecting the start and end times of the energy release condition, the low-pressure gas storage condition, the energy charging condition and the high-pressure gas storage condition according to the daily electricity price distribution.

[0083] By analyzing the daily electricity price distribution, the unit's operational schedule can be optimized based on the price. For example, during periods of low electricity prices, compressor unit 111 is preferably activated for charging, as this lowers the cost of electricity and significantly reduces energy storage costs. Conversely, during peak hours, when electricity prices are higher, turbine unit 112 can be activated for energy release, converting stored compressed air energy into electricity. This not only meets the grid's peak power demand but also maximizes economic benefits.

[0084] Figure 6 The cooling load changes of the compressor unit 111, the turbine unit 112 and the first heat exchanger 14 are arranged according to the start and end times of the energy release condition, the low-pressure gas storage condition, the energy charging condition and the high-pressure gas storage condition according to the electricity price distribution. Figure 6 The operating characteristics of the compressed air energy storage system 1 under different working conditions and the cooling load fluctuations of each component are depicted in a time series manner.

[0085] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that a specific feature, structure, material, or characteristic described in conjunction with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, illustrative uses of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0086] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to the embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the claims and their equivalents.

Claims

1. A compressed air energy storage power station active cooling system, characterized in that: include: A compressor unit (111) and a turbine unit (112), wherein a gas flow passage (113) is provided between the compressor unit (111) and the turbine unit (112); A cooling circuit (12), wherein a circulating cooling medium is provided in the cooling circuit (12), and the cooling circuit (12) is connected to the compressor unit (111) and the turbine unit (112); A heat storage circuit (13), wherein a circulating heat storage medium is provided in the heat storage circuit (13), and the heat storage circuit (13) comprises a main circuit (131), a first branch circuit (132), and a second branch circuit (133), wherein the first branch circuit (132) and the second branch circuit (133) are connected in parallel to each other and are respectively connected in series to the main circuit (131), a first circulation circuit is formed between the first branch circuit (132) and the main circuit (131), and a second circulation circuit is formed between the second branch circuit (133) and the main circuit (131); a first heat exchanger (14), the first heat exchanger (14) being arranged on the trunk line (131), the first heat exchanger (14) being provided with a first heat exchange flow channel and a second heat exchange flow channel, the first heat exchange flow channel being in communication with the trunk line (131), and the second heat exchange flow channel being in communication with the gas flow channel (113); a second heat exchanger (15), the second heat exchanger (15) being arranged in the first branch (132), the second heat exchanger (15) being provided with a third heat exchange channel and a fourth heat exchange channel, the third heat exchange channel being in communication with the first branch (132), and the fourth heat exchange channel being in communication with the cooling circuit (12); a high-temperature heat storage tank (16) and a low-temperature heat storage tank (17), wherein the high-temperature heat storage tank (16) and the low-temperature heat storage tank (17) are respectively used to store heat storage medium, and the high-temperature heat storage tank (16) and the low-temperature heat storage tank (17) are arranged in series on the trunk line (131); The main road (131) comprises a first main road (1311) and a second main road (1312); the first main road (1311) is located between the downstream of the high-temperature heat storage tank (16) and the upstream of the low-temperature heat storage tank (17); the second main road (1312) is located between the upstream of the high-temperature heat storage tank (16) and the downstream of the low-temperature heat storage tank (17); and the first branch road (132) and the second branch road (133) are arranged in parallel on the second main road (1312); The first heat exchanger (14) is constructed in a plurality, at least one of the first heat exchangers (14) is arranged on the first trunk (1311), and at least another of the first heat exchangers (14) is arranged on the second trunk (1312) and is located downstream of the first branch (132) and the second branch (133); The heat storage circuit (13) further comprises: a third branch (134), one end of the third branch (134) being connected to the low-temperature heat storage tank (17), and the other end of the third branch (134) being connected to the second trunk (1312) between the first branch (132) and the first heat exchanger (14); the first circulation circuit comprises a first circuit and a second circuit; the first circuit is formed between the high-temperature heat storage tank (16), the first trunk (1311), the low-temperature heat storage tank (17), the first branch (132) and the second trunk (1312); and the second circuit is formed between the low-temperature heat storage tank (17), the first branch (132), the third branch (134) and a portion of the second trunk (1312).

2. The active cooling system for a compressed air energy storage power station according to claim 1, characterized in that: The heat storage circuit (13) further comprises: a fourth branch (135), one end of the fourth branch (135) being connected to the first trunk line (1311) between the high-temperature heat storage tank (16) and the first heat exchanger (14), and the other end of the fourth branch (135) being connected to the first branch (132) upstream of the second heat exchanger (15).

3. The active cooling system for a compressed air energy storage power station according to claim 1, characterized in that: The cooling circuit (12) is provided with a main cooling pump (121) and an auxiliary cooling pump (122) which are arranged in parallel with each other.

4. A method for operating the active cooling system of a compressed air energy storage power station according to any one of claims 1 to 3, characterized in that: include: Determining the operating condition of the active cooling system of the compressed air energy storage power station and obtaining an actual cooling load after the low-pressure gas storage operating condition begins, and calculating an expected cooling load before the charging operating condition begins based on the actual cooling load and the weather temperature forecast value; The circulation mode of the heat storage circuit (13) is determined and selected according to the difference between the expected cooling load and the rated design working condition cooling load.

5. The method for operating the active cooling system of a compressed air energy storage power station according to claim 4, characterized in that: The circulation mode of the heat storage circuit (13) is determined and selected based on the difference between the expected cooling load and the rated design working condition cooling load, including: determining that a difference between the expected cooling load and the rated design operating condition cooling load is less than or equal to a first set difference, and starting the second circulation loop; determining that a difference between the expected cooling load and the rated design operating condition cooling load is greater than a first set difference and less than or equal to a second set difference, and starting the first circuit; It is determined that the difference between the expected cooling load and the rated design operating condition cooling load is greater than a second set difference, and the second circuit is started.

6. The method for operating the active cooling system of a compressed air energy storage power station according to claim 5, characterized in that: Also includes: Before the charging condition begins, the actual cooling load is obtained to determine whether the actual cooling load has dropped to the rated design condition cooling load, and the first circuit, the second circuit, or the second circulation circuit is started based on the determination result.

7. The method for operating the active cooling system of a compressed air energy storage power station according to claim 6, characterized in that: Determining, according to the determination result, to start the first loop, the second loop, or the second circulation loop includes: If the determination result is yes, then starting the second circulation loop; If the determination result is no, the second circuit is started and it is determined whether to start the first circuit according to the current electricity price.

8. The method for operating the active cooling system of a compressed air energy storage power station according to claim 4, characterized in that: The operating method further comprises: after the low-pressure gas storage condition begins, obtaining the liquid level of the high-temperature heat storage tank (16), and determining, based on the liquid level of the high-temperature heat storage tank (16), whether it is necessary to cool the heat storage medium in the high-temperature heat storage tank (16) and transport it to the low-temperature heat storage tank (17).

9. The method for operating the active cooling system of a compressed air energy storage power station according to claim 4, characterized in that: The operating method further includes: selecting the start and end times of the energy release condition, the low-pressure gas storage condition, the energy charging condition and the high-pressure gas storage condition according to the daily electricity price distribution.

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