Compressed air energy storage system with heat exchange subsystem on turbine side and method of operation thereof

Abstract

The application discloses a compressed air energy storage system with a heat exchange subsystem attached to a turbine side and a running method thereof. The compressed air energy storage system comprises a turbine subsystem, a heat exchange subsystem and a first heat exchanger. The turbine subsystem comprises a plurality of first turbines connected in series. The heat exchange subsystem comprises a first compressor and a first cooler. The first compressor is used for compressing a second medium. The first cooler is connected to the exhaust side of the first compressor. The first heat exchanger comprises a first heat exchange channel and a second heat exchange channel. The first heat exchange channel is connected between two first turbines. The second heat exchange channel is connected between the exhaust side of the first compressor and the first cooler. Thus, the heat exchange subsystem is arranged to enable the second medium compressed by the first compressor to exchange heat with the first medium in the first heat exchange channel at the first heat exchanger, thereby increasing the temperature of the first medium, which is conducive to increasing the work amount of the turbine subsystem and the power generation amount of the turbine subsystem.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of compressed air energy storage, and in particular to a compressed air energy storage system with a heat exchange subsystem attached to the turbine side and a method for operating the same. BACKGROUND

[0002] With the development of energy storage technology, advanced adiabatic compressed air energy storage (AA-CAES) has attracted extensive attention from relevant scholars and research institutions at home and abroad due to its long service life, cleanliness, environmental protection and other characteristics.

[0003] In the expansion turbine process of the compressed air energy storage system, the gas discharged by each stage of turbine needs to be reheated. In the related art, the reheating efficiency of the gas discharged by each stage of turbine in the expansion turbine process is low, which affects the power generation efficiency of the compressed air energy storage system. SUMMARY

[0004] The present application aims to at least solve one of the technical problems existing in the prior art. To this end, the present application provides a compressed air energy storage system with a heat exchange subsystem attached to the turbine side, the reheating efficiency of the first medium discharged by the first turbine of the compressed air energy storage system is high, which is conducive to improving the power generation capacity of the compressed air energy storage system.

[0005] The compressed air energy storage system with a heat exchange subsystem attached to the turbine side according to the embodiments of the present application comprises: a turbine subsystem, the turbine subsystem comprising a plurality of first turbines, the plurality of first turbines being connected in series in turn and being used for converting fluid energy of a first medium into mechanical energy; a heat exchange subsystem, the heat exchange subsystem comprising a first compressor and a first cooler, the first compressor being used for compressing a second medium, and the first cooler being connected to the exhaust side of the first compressor and being used for cooling the second medium; a first heat exchanger, the first heat exchanger comprising a first heat exchange channel and a second heat exchange channel, the first heat exchange channel being connected between two first turbines, the second heat exchange channel being connected between the exhaust side of the first compressor and the first cooler, and the first medium being capable of exchanging heat with the second medium at the first heat exchanger.

[0006] According to the compressed air energy storage system with a heat exchange subsystem on the turbine side in the embodiment of the present application, the heat exchange subsystem is arranged, and the first compressor is communicated with the second heat exchange channel of the first heat exchanger, so that the second medium compressed by the first compressor can be heat-exchanged with the first medium discharged by the first turbine in the first heat exchange channel at the first heat exchanger, and the temperature of the first medium is increased, thereby facilitating to increase the work amount of the turbine subsystem and the power generation amount of the turbine subsystem. The first cooler is arranged at the outlet side of the second heat exchange channel, so as to reduce the temperature of the second medium discharged from the second heat exchange channel, to prevent the second medium from being overheated, and to facilitate to improve the working efficiency and service life of the first compressor, thereby facilitating to improve the working efficiency and service life of the heat exchange subsystem.

[0007] According to some embodiments of the present application, the heat exchange subsystem is provided with a plurality of groups of the first compressor and the first cooler, and the first heat exchanger is connected between each group of the first compressor and the first cooler.

[0008] According to some embodiments of the present application, the first heat exchanger is a plurality of, and the first heat exchange channel of each first heat exchanger is connected between two adjacent first turbines.

[0009] According to some embodiments of the present application, the heat exchange subsystem further comprises a second compressor, an inlet side of the second compressor being communicated with the first cooler; a second heat exchanger, the second heat exchanger having a first flow channel, one end of the first flow channel being communicated with an outlet side of the second compressor, the second heat exchange channel of one of the plurality of first heat exchangers being connected between the second compressor and the first flow channel of the second heat exchanger; and a second turbine, the second turbine being communicated with the other end of the first flow channel, and the second turbine being used for converting the fluid energy of the second medium into mechanical energy.

[0010] According to some embodiments of the present application, the second heat exchanger is further provided with a second flow channel, one end of the second flow channel being connected with the second turbine, and the second medium flowing through the second turbine can flow into the second flow channel.

[0011] According to some embodiments of the present application, the heat exchange subsystem further comprises a gas supply channel, the gas supply channel being used for supplying the second medium to the first compressor, and the gas supply channel being communicated with the other end of the second flow channel.

[0012] According to some embodiments of the present application, the heat exchange subsystem further comprises a pre-cooler, the pre-cooler being arranged in the gas supply channel, and the pre-cooler being used for cooling the second medium in the gas supply channel.

[0013] According to some embodiments of the present application, in the air supply path of the air supply channel, the communication position of the second flow channel with the air supply channel is arranged upstream of the matching position of the air supply channel with the pre-cooler.

[0014] According to some embodiments of the present application, the compressed air energy storage system further comprises a compression subsystem, the second heat exchanger is further provided with a third flow channel, the third flow channel accesses the compression subsystem and is used for passing a third medium in the compression subsystem, and the third medium is adapted to transfer heat on the side of the compression subsystem to the second medium in the first flow channel.

[0015] According to some embodiments of the present application, the second medium is carbon dioxide.

[0016] A second object of the present application is to provide a method for operating a compressed air energy storage system with a turbine side attached heat exchange subsystem.

[0017] According to the method for operating the compressed air energy storage system with a turbine side attached heat exchange subsystem according to the embodiments of the present application, the compressed air energy storage system is the compressed air energy storage system with a turbine side attached heat exchange subsystem described above, and the method comprises: when the heat exchange subsystem is in a compression stage, the second medium is transported into the turbine subsystem and exchanges heat with the turbine subsystem; when the heat exchange subsystem is in an expansion stage, the second medium transported into the turbine subsystem flows back to the heat exchange subsystem, and the heat exchange subsystem generates electricity.

[0018] According to the method for operating the compressed air energy storage system with a turbine side attached heat exchange subsystem according to the embodiments of the present application, by controlling the flow of the second medium according to the operating state of the heat exchange system, the work amount and the power generation amount of the turbine subsystem can be improved, and additional power generation of the heat exchange subsystem can be realized to further improve the power generation amount of the compressed air energy storage system with a turbine side attached heat exchange subsystem.

[0019] Additional aspects and advantages of the present application will be in part apparent and in part pointed out hereinafter. BRIEF DESCRIPTION OF DRAWINGS

[0020] The above and / or additional aspects and advantages of the present application will become apparent and be readily appreciated from the following description, taken in conjunction with the accompanying drawings, in which:

[0021] Figure 1 A partial structural schematic diagram of the compressed air energy storage system with a turbine side attached heat exchange subsystem according to the embodiments of the present application;

[0022] Figure 2 A structural diagram of the second heat exchanger according to the embodiments of the present application.

[0023] Reference signs:

[0024] compressed air energy storage system 100,

[0025] turbine subsystem 110, first turbine 111, first-stage first turbine 1, second-stage first turbine 2, third-stage first turbine,

[0026] heat exchange subsystem 120, first compressor 121, first cooler 122, second compressor 123,

[0027] second heat exchanger 124, first flow passage 1241, second flow passage 1242, third flow passage 1243,

[0028] second turbine 125, gas supply passage 126, precooler 127,

[0029] first heat exchanger 130, first-stage first heat exchanger 131, second-stage first heat exchanger 132,

[0030] third heat exchanger 141, cold storage tank 142. DETAILED DESCRIPTION

[0031] Embodiments of the present application are described below in detail with reference to the accompanying drawings, in which like or similar elements are denoted by like or similar reference symbols throughout the drawings. The embodiments described below are examples for explaining the present application and are not intended to be limiting of the present application.

[0032] In the description of the present application, it is to be understood that the orientation or positional relationship indicated by the terms "inner", "outer", and the like is based on the orientation or positional relationship shown in the drawings, and is merely for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the present application. In addition, the features defined with "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, unless otherwise specified and limited, the term "a plurality of" means two or more.

[0033] In the description of the present application, it should be noted that, unless otherwise specified and limited, the terms "mounting", "connection", "connecting" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0034] Reference will now be made to Figure 1 and Figure 2 A compressed air energy storage system 100 with a heat exchange subsystem 120 attached to the turbine side according to an embodiment of the present application is described.

[0035] Reference will now be made to Figure 1 A compressed air energy storage system 100 with a heat exchange subsystem 120 attached to the turbine side according to an embodiment of the present application is described.

[0036] The compressed air energy storage system 100 further comprises the heat exchange subsystem 120 and the first heat exchanger 130, the heat exchange subsystem 120 comprises a first compressor 121 and a first cooler 122, the first compressor 121 is used for compressing a second medium, and the first cooler 122 is connected to the exhaust side of the first compressor 121 and is used for cooling the second medium, the first heat exchanger 130 comprises a first heat exchange passage and a second heat exchange passage, the first heat exchange passage is connected between two first turbines 111 in series, and the second heat exchange passage is connected between the exhaust side of the first compressor 121 and the first cooler 122, and the first medium can exchange heat with the second medium at the first heat exchanger 130.

[0037] The first heat exchange passage of the first heat exchanger 130 connects two first turbines 111 in series, and the first medium discharged from one of the two first turbines 111 in series can enter the other first turbine 111 through the first heat exchange passage, at the same time, the second heat exchange passage of the first heat exchanger 130 is connected to the exhaust side of the first compressor 121, and the second medium compressed by the first compressor 121 can enter the second heat exchange passage, and the second medium entering the second heat exchange passage can exchange heat with the first medium in the first heat exchanger 130 at the first heat exchanger 130 to increase the temperature of the first medium, thereby facilitating to increase the work amount of the turbine subsystem 110 and the power generation amount of the turbine subsystem 110.

[0038] By arranging the first cooler 122 at the outlet side of the second heat exchange passage, the temperature of the second medium discharged from the second heat exchange passage is reduced to prevent overheating of the second medium, and the working efficiency and service life of the first compressor 121 are improved, thereby facilitating to improve the working efficiency and service life of the heat exchange subsystem 120.

[0039] The compressed air energy storage system 100 of the turbine side attached with the heat exchange subsystem 120 according to the embodiment of the present application, by setting the heat exchange subsystem 120, and making the first compressor 121 communicate with the second heat exchange passage of the first heat exchanger 130, so that the second medium compressed by the first compressor 121 can exchange heat with the first medium discharged by the first turbine 111 in the first heat exchange passage at the first heat exchanger 130, to improve the temperature of the first medium, thereby facilitating to improve the work amount of the turbine subsystem 110, and improve the power generation amount of the turbine subsystem 110, by setting the first cooler 122 at the outlet side of the second heat exchange passage, to reduce the temperature of the second medium discharged from the second heat exchange passage, to prevent the second medium from overheating, and facilitate to improve the working efficiency and service life of the first compressor 121, thereby facilitating to improve the working efficiency and service life of the heat exchange subsystem 120.

[0040] As shown in the figure, Figure 1 In some embodiments of the present application, the heat exchange subsystem 120 is provided with multiple groups of first compressors 121 and first coolers 122, and the first heat exchanger 130 is connected between each group of first compressors 121 and first coolers 122.

[0041] Exemplarily, the first heat exchanger 130 is arranged between two first turbines 111 arranged in series in the multiple first turbines 111, and the two first turbines 111 arranged in series can communicate through the first heat exchange passage. By connecting the first heat exchanger 130 between each group of first compressors 121 and first coolers 122 in the heat exchange subsystem 120, the temperature of the first medium discharged by each first turbine 111 with the first heat exchange passage connected can be improved, thereby facilitating to further improve the work amount of the turbine subsystem 110, and improve the power generation amount of the turbine subsystem 110, while preventing the second medium discharged by each first compressor 121 from overheating, and facilitating to improve the working efficiency and service life of the first compressor 121, thereby facilitating to improve the working efficiency and service life of the heat exchange subsystem 120.

[0042] Referring to Figure 1 In some embodiments of the present application, the first heat exchanger 130 is multiple, and the first heat exchange passage of each first heat exchanger 130 is connected between two adjacent first turbines 111.

[0043] Exemplarily, the turbine subsystem 110 can include a first-stage first turbine 1, a second-stage first turbine 2 and a third-stage first turbine 3 arranged in series. The first-stage first turbine 1 is connected with the gas storage tank, the second-stage first turbine 2 is connected with the first-stage first turbine 1 and the third-stage first turbine 3 in series, and the third-stage first turbine is connected with the generator.

[0044] The first heat exchanger 130 includes a first-stage heat exchanger 131 and a second-stage first heat exchanger 132. The first-stage heat exchanger 131 is arranged between the first-stage first turbine 1 and the second-stage first turbine 2, and the second-stage first heat exchanger 132 is arranged between the second-stage first turbine 2 and the third-stage first turbine 3.

[0045] That is to say, the number of the first heat exchangers 130 can be one less than the number of the first turbines 111 , which is beneficial for simplifying the structure of the turbine subsystem 110 and reducing the production cost of the compressed air energy storage system 100 .

[0046] like Figure 1 As shown, in some embodiments of the present invention, the heat exchange subsystem 120 further includes: a second compressor 123, and the air intake side of the second compressor 123 is connected to the first cooler 122. By connecting the air intake side of the second compressor 123 to the first cooler 122, the temperature of the second medium entering the second compressor 123 is regulated through the first cooler 122, thereby preventing the temperature of the second medium from being higher than the upper temperature limit that the second compressor 123 can withstand, thereby protecting the second compressor 123.

[0047] Reference Figure 1 The heat exchange subsystem 120 also includes a second heat exchanger 124, the second heat exchanger 124 has a first circulation channel 1241, and one end of the first circulation channel 1241 is connected to the exhaust side of the second compressor 123, and the second heat exchange channel of one of the multiple first heat exchangers 130 is connected between the second compressor 123 and the first circulation channel 1241 of the second heat exchanger 124.

[0048] For example, the exhaust side of the second compressor 123 can be connected to the second heat exchange channel of the above-mentioned secondary first heat exchanger 132. After the second medium discharged by the second compressor 123 enters the second heat exchange channel of the secondary first heat exchanger 132, it exchanges heat with the first medium discharged by the secondary first turbine 2 entering the first heat exchange channel. After heat exchange at the secondary first heat exchanger 132, the first medium further flows into the first circulation channel 1241 in the second heat exchanger 124.

[0049] Combine Figure 1 and Figure 2 The heat exchange subsystem 120 further includes a second turbine 125 , which is connected to the other end of the first flow channel 1241 , and is configured to convert the fluid energy of the second medium into mechanical energy.

[0050] That is, the first medium after heat exchange at the secondary first heat exchanger 132 further flows into the first flow passage 1241 in the second heat exchanger 124 and flows through the first flow passage 1241 to the second turbine 125, and the second turbine 125 converts the second fluid energy of the second medium into mechanical energy and is used for output power generation.

[0051] Therefore, the heat exchange subsystem 120 can realize the power generation function, so as to further improve the power generation efficiency of the compressed air energy storage system 100.

[0052] When the temperature of the first medium discharged by the primary first turbine 1 is higher than the temperature of the first medium discharged by the secondary first turbine 2, the temperature of the second medium discharged by the first compressor 121 is higher than the temperature of the gas discharged by the second compressor 123, so as to ensure that the heat exchange subsystem 120 can meet the heat exchange demand of the plurality of first turbines 111 in the turbine subsystem 110.

[0053] In combination with Figure 1 and Figure 2 In some embodiments of the present application, the second heat exchanger 124 is further provided with a second flow passage 1242, one end of the second flow passage 1242 is connected with the second turbine 125, and the second medium flowing through the second turbine 125 can flow into the second flow passage 1242.

[0054] That is, the gas inlet end of the second flow passage 1242 is connected with the exhaust end of the second turbine 125, so that the second medium flowing out of the second turbine 125 can flow into the second flow passage 1242 in the second heat exchanger 124, so as to realize the recovery of the second medium, which is conducive to reducing the operation cost of the heat exchange subsystem 120.

[0055] Referring to Figure 1 In some embodiments of the present application, the heat exchange subsystem 120 further comprises a gas supply passage 126, the gas supply passage 126 is used for supplying the second medium to the first compressor 121, and the gas supply passage 126 is in communication with the other end of the second flow passage 1242.

[0056] Exemplarily, the gas supply passage 126 can be connected with an external gas source, so that the external gas source can deliver the second medium to the first compressor 121 through the gas supply passage 126, and at the same time, the gas supply passage 126 is also connected with the gas outlet end of the second flow passage 1242, the second medium flowing into the second flow passage 1242 from the second turbine 125 can further flow into the gas supply passage 126 and flow into the first compressor 121 through the gas supply passage 126, so as to realize the cyclic reuse of the second medium, which is conducive to saving the second medium, thereby reducing the operation cost of the heat exchange subsystem 120, and further saving the operation cost of the compressed air energy storage system 100.

[0057] It should be noted that when the heat exchange subsystem 120 is provided with multiple groups of the first compressor 121 and the first cooler 122, the gas supply channel 126 is in communication with the gas inlet side of the first compressor 121 in the group of the first compressor 121 at the end of the multiple groups of the first compressor 121 and the first cooler 122 arranged in series.

[0058] Referring to Figure 1 In some embodiments of the present application, the heat exchange subsystem 120 further comprises a pre-cooler 127, which is arranged in the gas supply channel 126 and is used to cool the second medium in the gas supply channel 126, so as to prevent the temperature of the second medium delivered by the external gas source from being higher than the upper limit of the temperature of the first compressor 121, to ensure that the second medium delivered by the gas supply channel 126 to the first compressor 121 can meet the temperature requirement of the first compressor 121, to prevent the second medium entering the first compressor 121 from being overheated, and to be conducive to improving the working efficiency and service life of the first compressor 121, thereby being conducive to improving the working efficiency and service life of the heat exchange subsystem 120.

[0059] As Figure 1 shown, in some embodiments of the present application, the communication position of the second flow channel 1242 with the gas supply channel 126 is arranged upstream of the matching position of the gas supply channel 126 and the pre-cooler 127 in the gas supply path of the gas supply channel 126, that is, the pre-cooler 127 can cool the second medium flowing from the second flow channel 1242 to the gas supply channel 126, to prevent the temperature of the second medium flowing from the second flow channel 1242 into the gas supply channel 126 from being higher than the upper limit of the temperature of the first compressor 121, so as to prevent the second medium entering the first compressor 121 from being overheated.

[0060] At the same time, since the second medium discharged from the second flow channel 1242 and the second medium delivered by the external gas source are both delivered to the first compressor 121 through the gas supply channel 126, by arranging the pre-cooler 127, it is conducive to ensuring the consistency of the temperature of the second medium delivered to the first compressor 121, thereby being conducive to ensuring the working performance of the first compressor 121.

[0061] In combination Figure 1 and Figure 2 In some embodiments of the present application, the compressed air energy storage system 100 further comprises a compression subsystem, and the second heat exchanger 124 is further provided with a third flow channel 1243, which is connected to the compression subsystem and is used for the third medium in the compression subsystem to pass through, and the third medium is adapted to transfer the heat on the side of the compression subsystem to the second medium in the first flow channel 1241.

[0062] Exemplarily, the compression subsystem comprises a plurality of third compressors, each of which is configured to compress the first medium, and the first medium compressed by the plurality of third compressors can be discharged into the gas storage tank. The compression subsystem further comprises a third heat exchanger 141, each of the plurality of third compressors is provided with a corresponding third heat exchanger 141, and the third heat exchanger 141 is provided with a third medium to adjust the temperature of the first medium discharged by the third compressors, and the third medium can collect the waste heat of the first medium discharged by the third compressors.

[0063] Further, the third heat exchanger 141 is provided with a passage in communication with the third flow passage 1243, and the third medium can enter the third flow passage 1243 and exchange heat with the second medium in the first flow passage 1241 to increase the temperature of the second medium entering the second turbine 125 from the first flow passage 1241, thereby improving the power generation efficiency of the heat exchange subsystem 120.

[0064] Meanwhile, the third medium in the third flow passage 1243 can exchange heat with the second medium discharged from the second turbine 125 and entering the second flow passage 1242 to increase the temperature of the second medium flowing back to the first compressor 121, i.e., to increase the suction temperature of the first compressor 121, which is conducive to improving the heat exchange efficiency of the heat exchange subsystem 120.

[0065] Therefore, by providing the second heat exchanger 124 and connecting the third flow passage 1243 in the second heat exchanger 124 to the compression subsystem, the waste heat of the compression subsystem can be recovered, which is conducive to improving the power generation efficiency of the compressed air energy storage system 100 and saving the energy consumption of the compressed air energy storage system 100.

[0066] It should be noted that the third heat exchanger 141 in communication with the third flow passage 1243 can be any one of a plurality of third heat exchangers 141.

[0067] Reference Figure 1 In some embodiments of the present application, the compression subsystem further comprises a cold storage tank 142, the cold storage tank 142 is in communication with the third flow passage 1243, and the third medium in the third flow passage 1243 can further flow into the cold storage tank 142 after exchanging heat with the second medium discharged from the second turbine 125 and entering the second flow passage 1242, so as to realize the recovery of the third medium.

[0068] In some embodiments of the present application, the second medium is carbon dioxide. Carbon dioxide has good thermodynamic performance (high volumetric refrigeration capacity), environmental protection, and small subcritical cycle pressure ratio, and therefore, configuring the second medium as carbon dioxide is conducive to achieving efficient refrigeration and heat exchange of the second medium, and can achieve faster heat transfer, which is conducive to improving the heat exchange effect and efficiency of the heat exchange subsystem 120, thereby improving the power generation efficiency of the compressed air energy storage system 100.

[0069] When the temperature and pressure of carbon dioxide are above the critical temperature and critical pressure, the carbon dioxide is in a supercritical state. When the temperature and pressure of carbon dioxide are below the critical temperature and critical pressure, the carbon dioxide is in a subcritical state. The transition of carbon dioxide from a subcritical state to a supercritical state is referred to as transcritical of carbon dioxide.

[0070] When the carbon dioxide flows through the precooler 127 and the first compressor 121, the precooler 127 and the first compressor 121 can convert the carbon dioxide into a transcritical state and use it for refrigeration and heat exchange. Similarly, when the carbon dioxide flows through the first cooler 122 and the second compressor 123, the first cooler 122 and the second compressor 123 can convert the carbon dioxide into a transcritical state and use it for refrigeration and heat exchange. Transcritical carbon dioxide has good thermodynamic performance, which is conducive to further improving the heat exchange efficiency and effect of the heat exchange subsystem 120. In addition, the compression power of transcritical carbon dioxide is low, which is conducive to reducing the operating cost of the heat exchange subsystem 120.

[0071] In addition, the first medium is air, and the third medium can be water or other heat-conducting oil.

[0072] The models of the components in the heat exchange subsystem 120 described in the embodiments of the present application are briefly described below.

[0073] The temperature variation model of the first compressor 121 (or the second compressor 123) is as follows:

[0074]

[0075] wherein, T out is the temperature of the second medium at the outlet of the first compressor 121 (or the second compressor 123), in K; T in is the inlet temperature of the first compressor 121 (or the second compressor 123), in K; π c is the compression ratio of the first compressor 121 (or the second compressor 123); and n is the adiabatic index.

[0076] The output power model of the first compressor 121 (or the second compressor 123) is as follows:

[0077] W c=C p,a m a (T out -T in )

[0078] wherein, W c is the power consumption of the first compressor 121 (or the second compressor 123), in units of kW; C p,a is the specific heat capacity of the second medium, in units of J / (kg·K); m a is the mass of air, in units of kg.

[0079] The outlet temperature model of the second turbine 125 is as follows:

[0080]

[0081] wherein, T out is the temperature of the second medium at the outlet of the second turbine 125, in units of K; T in is the inlet temperature of the second turbine 125, in units of K; π t is the expansion ratio of the second turbine 125, and n is the adiabatic index.

[0082] The output power model of the second turbine 125 is as follows:

[0083] W t =C p,a m a (T in -T out )

[0084] wherein, W t is the output power of the second turbine 125, in units of kW; C p,a is the specific heat capacity of the second medium, in units of J / (kg·K); m a is the mass of the second medium, in units of kg; T out is the temperature of the second medium at the outlet of the second turbine 125, in units of K; T in is the inlet temperature of the second turbine 125, in units of K.

[0085] The heat exchange amount model of the second heat exchanger 124 is as follows:

[0086] Q H0 =m(h 02 -h 01 )

[0087] wherein, m is the mass flow rate of the second medium, in units of kg / h; h 02 is the specific enthalpy of the second medium discharged from the second heat exchanger 124 and entering the second turbine 125, and h 01The specific enthalpy of the second medium flowing out from the first heat exchanger 130 and into the second heat exchanger 124, both in kj / kg.

[0088] The refrigeration capacity model of the first cooler 122 (or the pre-cooler 127) is as follows:

[0089] Q cold = m cold (h cold2 -h cold1 )

[0090] wherein m cold is the mass flow of the second medium, in kg / h; h cold2 is the specific enthalpy of the second medium flowing out from the first cooler 122 (or the pre-cooler 127), and h cold1 is the specific enthalpy of the second medium flowing into the first cooler 122 (or the pre-cooler 127), both in kj / kg.

[0091] The operation method of the compressed air energy storage system with a heat exchange subsystem on the turbine side according to the embodiment of the present application, the compressed air energy storage system 100 is the compressed air energy storage system 100 with a heat exchange subsystem 120 on the turbine side as described above, and the operation method comprises: when the heat exchange subsystem 120 is in the compression stage, the second medium is delivered into the turbine subsystem 110 and exchanged with the turbine subsystem 110; when the heat exchange subsystem 120 is in the expansion stage, the second medium delivered into the turbine subsystem 110 flows back into the heat exchange subsystem 120, and the heat exchange subsystem 120 generates electricity.

[0092] Specifically, when the heat exchange subsystem 120 is in the compression stage, the second medium is delivered into the first compressor 121 through the gas supply channel 126, and in the process, the pre-cooler 127 pre-cools the second medium, and when the temperature of the second medium stabilizes, the second medium enters the first compressor 121, the first compressor 121 compresses the second medium, the compressed second medium enters the second heat exchange channel of the primary first heat exchanger 131, and exchanges heat with the first medium in the first heat exchange channel of the primary first heat exchanger 131, and then the second medium flows from the second heat exchange channel of the primary first heat exchanger 131 to the second compressor 123, and in the process, the first cooler 122 cools the second medium, the cooled second medium enters the second compressor 123, the second compressor 123 further compresses the second medium, the second medium compressed by the second compressor 123 flows into the second heat exchange channel of the secondary first heat exchanger 132, and exchanges heat with the first medium in the first heat exchange channel of the secondary first heat exchanger 132, so as to increase the temperature of the first medium, thereby facilitating the increase of the work amount of the turbine subsystem 110 and the increase of the power generation amount of the turbine subsystem 110.

[0093] When the heat exchange subsystem 120 is in the expansion stage, the second medium flowing into the secondary first heat exchanger 132 flows into the first flow passage 1241 in the second heat exchanger 124, and further flows to the second turbine 125, and in the process, the second medium entering the first flow passage 1241 exchanges heat with the third medium in the third flow passage 1243 to recover waste heat in the compression subsystem, increase the temperature of the second medium entering the second turbine 125, and generate electricity when the second medium enters the second turbine 125. The second medium discharged from the second turbine 125 flows to the gas supply passage 126 through the second flow passage 1242, is pre-cooled by the pre-cooler 127, and further flows back to the first compressor 121 to perform the next cycle.

[0094] It should be noted that the heat exchange subsystem 120 described in the embodiments of the present application can be used to exchange heat with the first turbine 111 with a lower temperature discharged from the turbine subsystem 110, for example: when three first turbines 111 are arranged in series in the turbine subsystem 110, the heat exchange subsystem 120 can exchange heat with the first medium discharged from one first turbine 111 connected to the gas storage tank, or the heat exchange subsystem 120 can exchange heat with two first turbines 111 (which can also be understood as the first two first turbines 111 of the three first turbines 111 arranged in series) connected to the gas storage tank in sequence, to ensure that the heat exchange subsystem 120 can effectively heat the first medium discharged from the first turbine 111.

[0095] According to the operation method of the compressed air energy storage system 100 with a heat exchange subsystem 120 on the turbine side, by controlling the flow of the second medium according to the operating state of the heat exchange subsystem 120, the power output of the turbine subsystem 110 can be improved, the power generation of the turbine subsystem 110 can be improved, and additional power generation of the heat exchange subsystem 120 can be achieved to further improve the power generation of the compressed air energy storage system 100 with a heat exchange subsystem 120 on the turbine side.

[0096] In the description of the present specification, the description of the terms "one embodiment", "some embodiments", "exemplary embodiment", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the exemplary description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0097] While embodiments of the application have been shown and described, it is to be understood that the embodiments described are merely divergences of the principles and application of the present application and that numerous modifications, changes, substitutions, and alterations can be made thereto without departing from the spirit and scope of the present application, which is defined by the following claims and their equivalents.

Claims

1. A compressed air energy storage system with a heat exchange subsystem attached to the turbine side, characterized in that, The compressed air energy storage system comprises: a turbine subsystem (110) comprising a plurality of first turbines (111) connected in series and used for converting fluid energy of a first medium into mechanical energy; a heat exchange subsystem (120) comprising: a first compressor (121) used for compressing a second medium, and a first cooler (122) connected at an exhaust side of the first compressor (121) and used for cooling the second medium; a second compressor (123) having a gas inlet side communicated with the first cooler (122); a second heat exchanger (124) having a first flow passage (1241) with one end communicated with an exhaust side of the second compressor (123); a second turbine (125) communicated with the other end of the first flow passage (1241) and used for converting fluid energy of the second medium into mechanical energy; a plurality of first heat exchangers (130), each of which comprises a first heat exchange passage and a second heat exchange passage, the first heat exchange passage of each of the first heat exchangers (130) is connected between two adjacent first turbines (111), the second heat exchange passage of one of the first heat exchangers (130) is connected between the second compressor (123) and the first flow passage (1241), the second heat exchange passage of the rest of the first heat exchangers (130) is connected between the exhaust side of the first compressor (121) and the first cooler (122), and the first medium can exchange heat with the second medium at the first heat exchanger (130).

2. The compressed air energy storage system with a turbine-side attached heat exchange subsystem of claim 1, wherein, The heat exchange subsystem (120) is provided with a plurality of groups of the first compressor (121) and the first cooler (122), and the first heat exchanger (130) is connected between each group of the first compressor (121) and the first cooler (122).

3. The compressed air energy storage system with turbine-side attached heat exchange subsystem of claim 1, wherein, The second heat exchanger (124) is further provided with a second flow passage (1242) with one end connected with the second turbine (125), and the second medium flowing through the second turbine (125) can flow into the second flow passage (1242).

4. The compressed air energy storage system with turbine-side attached heat exchange subsystem of claim 3, wherein, The heat exchange subsystem (120) further comprises a gas supply passage (126) used for supplying the second medium to the first compressor (121), and the gas supply passage (126) is communicated with the other end of the second flow passage (1242).

5. The compressed air energy storage system with turbine-side attached heat exchanger subsystem of claim 4, wherein, The heat exchange subsystem (120) further comprises a precooler (127) arranged in the gas supply passage (126), and the precooler (127) is used for cooling the second medium in the gas supply passage (126).

6. The compressed air energy storage system with turbine-side attached heat exchange subsystem of claim 5, wherein, In the gas supply path of the gas supply passage (126), the communication position of the second flow passage (1242) with the gas supply passage (126) is arranged upstream of the matching position of the gas supply passage (126) and the precooler (127).

7. The turbo-side heat exchanger subsystem attached compressed air energy storage system of claim 3, wherein, The compressed air energy storage system further comprises a compression subsystem, the second heat exchanger (124) is further provided with a third flow passage (1243) connected to the compression subsystem and used for passing a third medium in the compression subsystem, and the third medium is adapted to transfer heat from the compression subsystem side to the second medium in the first flow passage (1241).

8. The turbo-side heat exchanger subsystem attached compressed air energy storage system of claim 1, wherein, The second medium is carbon dioxide.

9. A method of operating a compressed air energy storage system with a heat exchange subsystem attached to the turbine side, characterized in that, The compressed air energy storage system is the compressed air energy storage system with a heat exchange subsystem attached to a turbine side according to any one of claims 1-8, and the operation method comprises: When the heat exchange subsystem (120) is in the compression stage, the second medium is delivered into the turbine subsystem (110) and exchanges heat with the turbine subsystem (110); When the heat exchange subsystem (120) is in the expansion stage, the second medium delivered into the turbine subsystem (110) flows back to the heat exchange subsystem (120), and the heat exchange subsystem (120) generates electricity.

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