Compressed air energy storage system with heat exchange subsystem attached to turbine side and operation method of compressed air energy storage system

Abstract

The invention discloses a compressed air energy storage system with a heat exchange subsystem attached to the turbine side and an operation method thereof.The compressed air energy storage system comprises a turbine subsystem, the heat exchange subsystem and a first heat exchanger, the turbine subsystem comprises a plurality of first turbines which are sequentially connected in series, and 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 the two first turbines, and the second heat exchange channel is connected between the exhaust side of the first compressor and the first cooler. Therefore, by arranging the heat exchange subsystem, the second medium compressed by the first compressor can exchange heat with the first medium in the first heat exchange channel at the first heat exchanger, the temperature of the first medium is increased, and therefore the work amount of the turbine subsystem can be increased, and the generating capacity of the turbine subsystem can be increased.

Description

Technical Field

[0001] The present invention 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 a turbine side and an operation method thereof. Background Art

[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 operating life, cleanliness and environmental protection.

[0003] Among them, the gas discharged from each stage of the turbine in the expansion turbine process of the compressed air energy storage system needs to be reheated. In the related technology, the reheating efficiency of the gas discharged from each stage of the turbine in the expansion turbine process is low, which affects the power generation efficiency of the compressed air energy storage system. Summary of the invention

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

[0005] According to an embodiment of the present invention, a compressed air energy storage system with a heat exchange subsystem attached to the turbine side comprises: a turbine subsystem, wherein the turbine subsystem comprises a plurality of first turbines, wherein the plurality of first turbines are sequentially connected in series and are used to convert the fluid energy of a first medium into mechanical energy; a heat exchange subsystem, wherein the heat exchange subsystem comprises a first compressor and a first cooler, wherein the first compressor is used to compress a second medium, and the first cooler is connected to the exhaust side of the first compressor and is used to cool the second medium; a first heat exchanger, wherein the first heat exchanger comprises a first heat exchange channel and a second heat exchange channel, wherein the first heat exchange channel is connected between the two first turbines, and the second heat exchange channel is connected between the exhaust side of the first compressor and the first cooler, and the first medium can exchange heat with the second medium at the first heat exchanger.

[0006] According to the compressed air energy storage system with a heat exchange subsystem attached to the turbine side of an embodiment of the present invention, the heat exchange subsystem is set up, and the first compressor is connected to the second heat exchange channel of the first heat exchanger, so that the second medium compressed by the first compressor can be exchanged with the first medium discharged from the first turbine in the first heat exchange channel at the first heat exchanger to increase the temperature of the first medium, which is beneficial to increasing the work done by the turbine subsystem and the power generation of the turbine subsystem. By setting a first cooler on the outlet side of the second heat exchange channel to reduce the temperature of the second medium discharged from the second heat exchange channel, the second medium is prevented from overheating, and the working efficiency and service life of the first compressor are improved, thereby improving the working efficiency and service life of the heat exchange subsystem.

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

[0008] According to some embodiments of the present invention, there are a plurality of first heat exchangers, and the first heat exchange channel of each first heat exchanger is connected between two adjacently connected first turbines.

[0009] According to some embodiments of the present invention, the heat exchange subsystem also includes: a second compressor, the intake side of the second compressor is connected to the first cooler; a second heat exchanger, the second heat exchanger has a first circulation channel, and one end of the first circulation channel is connected to the exhaust side of the second compressor, the second heat exchange channel of one of the multiple first heat exchangers is connected between the second compressor and the first circulation channel of the second heat exchanger; a second turbine, the second turbine is connected to the other end of the first circulation channel, and the second turbine is used to convert the fluid energy of the second medium into mechanical energy.

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

[0011] According to some embodiments of the present invention, the heat exchange subsystem further includes an air supply channel, the air supply channel is used to supply the second medium to the first compressor, and the air supply channel is connected to the other end of the second circulation channel.

[0012] According to some embodiments of the present invention, the heat exchange subsystem further includes a precooler, which is disposed in the air supply channel and is used to cool the second medium in the air supply channel.

[0013] According to some embodiments of the present invention, in the air supply path of the air supply channel, the communication position between the second circulation channel and the air supply channel is arranged upstream of the matching position between the air supply channel and the precooler.

[0014] According to some embodiments of the present invention, the compressed air energy storage system also includes a compression subsystem, and the second heat exchanger is further provided with a third circulation channel, the third circulation channel is connected to the compression subsystem and is used for allowing a third medium in the compression subsystem to pass through, and the third medium is suitable for transferring heat from the compression subsystem side to the second medium in the first circulation channel.

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

[0016] The second object of the present invention is to provide an operating method for a compressed air energy storage system having a heat exchange subsystem attached to the turbine side.

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

[0018] According to the method of the compressed air energy storage system with a heat exchange subsystem attached to the turbine side according to an embodiment of the present invention, by controlling the flow of the second medium according to the operating state of the heat exchange system, it is beneficial to increase the work done and power generation of the turbine subsystem, and can realize additional power generation of the heat exchange subsystem to further increase the power generation of the compressed air energy storage system with a heat exchange subsystem attached to the turbine side.

[0019] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

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

[0022] Figure 2 This is a simplified structural diagram of the second heat exchanger described in an embodiment of the present invention.

[0023] Reference numerals:

[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] The second heat exchanger 124, the first circulation channel 1241, the second circulation channel 1242, the third circulation channel 1243,

[0028] The second turbine 125, the air supply channel 126, the precooler 127,

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

[0030] The third heat exchanger 141 and the cold storage tank 142 . DETAILED DESCRIPTION

[0031] Embodiments of the present invention are described in detail below, examples of which 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 only used to explain the present invention, and cannot be understood as limiting the present invention.

[0032] In the description of the present invention, it should be understood that the terms "inside", "outside", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying 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 a limitation on the present invention. In addition, features defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0033] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0034] Reference below Figure 1 and Figure 2 A compressed air energy storage system 100 is described in which a heat exchange subsystem 120 is attached to the turbine side according to an embodiment of the present invention.

[0035] Reference Figure 1 According to an embodiment of the present invention, the compressed air energy storage system 100 with a heat exchange subsystem 120 attached to the turbine side includes: a turbine subsystem 110, the turbine subsystem 110 is connected to an air storage tank (not shown) of the compressed air energy storage system 100, and the first medium in the air storage tank can be discharged into the first turbine 111 of the turbine subsystem 110, and the first turbine 111 can convert the fluid energy of the first medium into mechanical energy, wherein the turbine subsystem 110 includes a plurality of first turbines 111 arranged in series in sequence, which is beneficial to the mechanical energy output by the turbine subsystem 110.

[0036] The compressed air energy storage system 100 also includes a heat exchange subsystem 120 and a first heat exchanger 130. The heat exchange subsystem 120 includes a first compressor 121 and a first cooler 122. The first compressor 121 is used to compress the second medium, and the first cooler 122 is connected to the exhaust side of the first compressor 121 and is used to cool the second medium. The first heat exchanger 130 includes a first heat exchange channel and a second heat exchange channel. The first heat exchange channel is connected between the two first turbines 111, and the second heat exchange channel is connected between the exhaust side of the first compressor 121 and the first cooler 122. The first medium can exchange heat with the second medium at the first heat exchanger 130.

[0037] The first heat exchange channel of the first heat exchanger 130 connects the two first turbines 111 arranged in series, and the first medium discharged from one of the two first turbines 111 arranged in series can enter the other first turbine 111 through the first heat exchange channel. At the same time, the second heat exchange channel 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 channel, and the second medium entering the second heat exchange channel 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, which is beneficial to increase the work done by the turbine subsystem 110 and increase the power generation of the turbine subsystem 110.

[0038] By setting the first cooler 122 on the outlet side of the second heat exchange channel, the temperature of the second medium discharged from the second heat exchange channel is reduced to prevent the second medium from overheating, and it is beneficial to improve the working efficiency and service life of the first compressor 121, thereby helping to improve the working efficiency and service life of the heat exchange subsystem 120.

[0039] According to the compressed air energy storage system 100 with a heat exchange subsystem 120 attached to the turbine side of the embodiment of the present invention, the heat exchange subsystem 120 is set, and the first compressor 121 is connected to the second heat exchange channel of the first heat exchanger 130, so that the second medium compressed by the first compressor 121 can be heat exchanged with the first medium discharged from the first turbine 111 in the first heat exchange channel at the first heat exchanger 130, thereby increasing the temperature of the first medium, which is beneficial to increasing the work done by the turbine subsystem 110 and the power generation of the turbine subsystem 110. By setting the first cooler 122 on the outlet side of the second heat exchange channel to reduce the temperature of the second medium discharged from the second heat exchange channel, the second medium is prevented from overheating, and the working efficiency and service life of the first compressor 121 are improved, thereby improving the working efficiency and service life of the heat exchange subsystem 120.

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

[0041] Exemplarily, a first heat exchanger 130 is provided between two first turbines 111 arranged in series among the multiple first turbines 111, and the two first turbines 111 arranged in series can be connected through the first heat exchange channel. By connecting the first heat exchanger 130 between each group of first compressors 121 and the first cooler 122 in the heat exchange subsystem 120, the temperature of the first medium discharged from the first turbine 111 connected to the first heat exchange channel on each exhaust side can be increased, which is beneficial to further improve the work done by the turbine subsystem 110 and the power generation of the turbine subsystem 110. At the same time, it can prevent the second medium discharged from each first compressor 121 from overheating, and is beneficial to improving the working efficiency and service life of the first compressor 121, thereby facilitating improving the working efficiency and service life of the heat exchange subsystem 120.

[0042] Reference Figure 1 In some embodiments of the present invention, there are multiple first heat exchangers 130 , and the first heat exchange channel of each first heat exchanger 130 is connected between two adjacent first turbines 111 .

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

[0044] The first heat exchanger 130 includes a first-stage first heat exchanger 131 and a second-stage first heat exchanger 132. The first-stage first 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 to simplify the structure of the turbine subsystem 110 and reduce 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 also 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 adjusted through the first cooler 122 to prevent 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 a first heat exchanger 130 among the multiple first heat exchangers 130 is connected between the first circulation channel 1241 of the second compressor 123 and 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 from 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 from the secondary first turbine 2 entering the first heat exchange channel. After the heat exchange in the secondary first heat exchanger 132, the first medium further flows into the first circulation channel 1241 in the second heat exchanger 124.

[0049] Combination 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 used to convert the fluid energy of the second medium into mechanical energy.

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

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

[0052] Among them, when the temperature of the first medium discharged from the first stage first turbine 1 is higher than the temperature of the first medium discharged from the second stage first turbine 2, the temperature of the second medium discharged from the first compressor 121 is higher than the temperature of the gas discharged from the second compressor 123, so as to ensure that the heat exchange subsystem 120 can meet the heat exchange requirements of multiple first turbines 111 in the turbine subsystem 110.

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

[0054] That is to say, the air inlet end of the second circulation channel 1242 is connected to 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 circulation channel 1242 in the second heat exchanger 124 to achieve the recovery of the second medium, which is beneficial to reducing the operating cost of the heat exchange subsystem 120.

[0055] Reference Figure 1 In some embodiments of the present invention, the heat exchange subsystem 120 further includes an air supply channel 126 , which is used to supply the second medium to the first compressor 121 , and the air supply channel 126 is connected to the other end of the second circulation channel 1242 .

[0056] Exemplarily, the air supply channel 126 can be connected to an external air source so that the external air source can transport the second medium to the first compressor 121 through the air supply channel 126. At the same time, the air supply channel 126 is also connected to the air outlet end of the second circulation channel 1242. The second medium flowing into the second circulation channel 1242 from the second turbine 125 can further flow into the air supply channel 126 and flow into the first compressor 121 through the air supply channel 126 to achieve the recycling of the second medium, which is beneficial to saving the second medium, thereby helping to reduce the operating cost of the heat exchange subsystem 120, and further helping to save the operating 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 first compressors 121 and first coolers 122, the air supply channel 126 is connected to the intake side of a group of first compressors 121 located at the end of the multiple groups of first compressors 121 and first coolers 122 arranged in series.

[0058] Reference Figure 1 In some embodiments of the present invention, the heat exchange subsystem 120 also includes a precooler 127, which is arranged in the air supply channel 126, and the precooler 127 is used to cool the second medium in the air supply channel 126 to prevent the temperature of the second medium transported by the external air source from being higher than the upper temperature limit of the first compressor 121, and to ensure that the second medium transported to the first compressor 121 by the air supply channel 126 can meet the temperature requirement of the first compressor 121, and prevent the second medium entering the first compressor 121 from overheating, which is beneficial to improving the working efficiency and service life of the first compressor 121, thereby helping to improve the working efficiency and service life of the heat exchange subsystem 120.

[0059] like Figure 1 As shown, in some embodiments of the present invention, in the air supply path of the air supply channel 126, the connecting position between the second circulation channel 1242 and the air supply channel 126 is arranged upstream of the matching position of the air supply channel 126 and the precooler 127, that is, the precooler 127 can cool the second medium flowing from the second circulation channel 1242 to the air supply channel 126 to prevent the temperature of the second medium flowing from the second circulation channel 1242 to the air supply channel 126 from being higher than the upper temperature limit of the first compressor 121, so as to prevent the second medium entering the first compressor 121 from overheating.

[0060] At the same time, since the second medium discharged from the second circulation channel 1242 and the second medium delivered by the external air source are both delivered to the first compressor 121 through the air supply channel 126, the provision of the precooler 127 is beneficial to ensuring the consistency of the temperature of the second medium delivered to the first compressor 121, thereby ensuring the working performance of the first compressor 121.

[0061] Combination Figure 1 and Figure 2 In some embodiments of the present invention, the compressed air energy storage system 100 also includes a compression subsystem, and the second heat exchanger 124 is also provided with a third circulation channel 1243, the third circulation channel 1243 is connected to the compression subsystem, and is used for allowing the third medium in the compression subsystem to pass through, and the third medium is suitable for transferring heat on the compression subsystem side to the second medium in the first circulation channel 1241.

[0062] Exemplarily, the compression subsystem includes a multi-stage third compressor, each stage of the third compressor is used to compress the first medium, and the first medium compressed by the multi-stage third compressor can be discharged into the air storage tank. The compression subsystem also includes a third heat exchanger 141, and each stage of the third compressor is correspondingly provided with a third heat exchanger 141. The third medium flows through the third heat exchanger 141 to adjust the temperature of the first medium discharged by the third compressor, and the third medium can collect the waste heat of the first medium discharged by the third compressor.

[0063] Furthermore, the third heat exchanger 141 is provided with a channel connected to the third circulation channel 1243, and the third medium can enter the third circulation channel 1243 and exchange heat with the second medium in the first circulation channel 1241 to increase the temperature of the second medium entering the second turbine 125 from the first circulation channel 1241, so as to improve the power generation efficiency of the heat exchange subsystem 120.

[0064] At the same time, the third medium in the third circulation channel 1243 can exchange heat with the second medium discharged from the second turbine 125 and entering the second circulation channel 1242 to increase the temperature of the second medium flowing back to the first compressor 121, that is, to increase the suction temperature of the first compressor 121, which is beneficial to improving the heat exchange efficiency of the heat exchange subsystem 120.

[0065] Therefore, by setting up the second heat exchanger 124 and connecting the third flow channel 1243 in the second heat exchanger 124 to the compression subsystem to realize waste heat recovery of the compression subsystem, it is beneficial to improve the power generation efficiency of the compressed air energy storage system 100 and save the energy consumption of the compressed air energy storage system 100.

[0066] It should be noted that the third heat exchanger 141 connected to the third circulation channel 1243 may be any one of the plurality of third heat exchangers 141 .

[0067] Reference Figure 1 In some embodiments of the present invention, the compression subsystem also includes a cold storage tank 142, which is connected to the third circulation channel 1243. After the third medium in the third circulation channel 1243 exchanges heat with the second medium discharged from the second turbine 125 and entering the second circulation channel 1242, it can further flow into the cold storage tank 142 to achieve recovery of the third medium.

[0068] In some embodiments of the present invention, the second medium is carbon dioxide, which has good thermal properties (high volumetric refrigeration capacity), environmental protection, and a small subcritical cycle pressure ratio. Therefore, configuring the second medium as carbon dioxide is beneficial to achieving efficient refrigeration and heat exchange effects of the second medium, and can achieve faster heat transfer, which is beneficial to improving the heat exchange effect and heat exchange efficiency of the heat exchange subsystem 120, thereby helping to improve the power generation efficiency of the compressed air energy storage system 100.

[0069] Among them, 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 the subcritical state to the supercritical state is called transcriticality of carbon dioxide.

[0070] When carbon dioxide flows through the precooler 127 and the first compressor 121, the precooler 127 and the first compressor 121 can convert carbon dioxide into a transcritical state and use it for refrigeration and heat exchange. Similarly, when carbon dioxide flows through the first cooler 122 and the second compressor 123, the first cooler 122 and the second compressor 123 can convert carbon dioxide into a transcritical state and use it for refrigeration and heat exchange. Transcritical carbon dioxide has good thermal properties, which is beneficial to further improve the heat exchange efficiency and heat exchange effect of the heat exchange subsystem 120, and the compression power of transcritical carbon dioxide is low, which is beneficial to reduce 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 transfer oil.

[0072] The following briefly describes the models of the various components in the heat exchange subsystem 120 according to the embodiment of the present invention.

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

[0074]

[0075] Among them, 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 intake air 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); 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] Among them, W c is the power consumption of the first compressor 121 (or the second compressor 123), in kW; C p,a is the specific heat capacity of the second medium, in J / (kg·K); m a is the air mass in kg.

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

[0080]

[0081] Among them, T out is the temperature of the second medium at the outlet of the second turbine 125, in K; T in is the intake air temperature of the second turbine 125, in 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] Among them, W t is the output power of the second turbine 125, in kW; C p,a is the specific heat capacity of the second medium, in J / (kg·K); m a is the mass of the second medium, in kg; T out is the temperature of the second medium at the outlet of the second turbine 125, in K; T in is the intake air temperature of the second turbine 125, in K.

[0085] The heat transfer 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 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, h 01is the specific enthalpy of the second medium flowing out of the first heat exchanger 130 and entering the second heat exchanger 124, and the unit is kj / kg.

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

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

[0090] Among them, m cold is the mass flow rate of the second medium, in kg / h; h cold2 is the specific enthalpy of the second medium discharged from the first cooler 122 (or precooler 127), h cold1 is the specific enthalpy of the second medium entering the first cooler 122 (or precooler 127), and the unit is kj / kg.

[0091] According to the operating method of the compressed air energy storage system with a heat exchange subsystem attached to the turbine side of an embodiment of the present invention, the compressed air energy storage system 100 is the above-mentioned compressed air energy storage system 100 with a heat exchange subsystem 120 attached to the turbine side, and the operating method includes: when the heat exchange subsystem 120 is in the compression stage, the second medium is transported to 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 transported to the turbine subsystem 110 flows back to 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 transported to the first compressor 121 through the air supply channel 126, and in this process, the precooler 127 precools the second medium. When the temperature of the second medium stabilizes, it enters the first compressor 121, and the first compressor 121 compresses the second medium. The compressed second medium enters the second heat exchange channel in the first heat exchanger 131 of the first stage, and exchanges heat with the first medium in the first heat exchange channel in the first heat exchanger 131 of the first stage, and then the second medium is discharged from the second heat exchange channel of the first heat exchanger 131 of the first stage. The second medium flows in the channel to the second compressor 123, and in the process, the first cooler 122 cools the second medium, and the cooled second medium enters the second compressor 123, and 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 in 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 to increase the temperature of the first medium, which is beneficial to increase the work done by the turbine subsystem 110 and increase the power generation 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 circulation channel 1241 in the second heat exchanger 124, and further flows to the second turbine 125. In this process, the second medium entering the first circulation channel 1241 exchanges heat with the third medium in the third circulation channel 1243 to recover the waste heat in the compression subsystem and increase the temperature of the second medium entering the second turbine 125. After the second medium enters the second turbine 125, it generates electricity, and then the second medium discharged from the second turbine 125 flows through the second circulation channel 1242 to the air supply channel 126, and after being pre-cooled by the precooler 127, it further flows back to the first compressor 121 for the next cycle.

[0094] It should be noted that the heat exchange subsystem 120 described in the embodiment of the present invention 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 a first turbine 111 connected to the gas tank, or the heat exchange subsystem 120 can exchange heat with two first turbines 111 connected to the gas tank in sequence (which can also be understood as the first two stages of the three first turbines 111 arranged in series) to ensure that the heat exchange subsystem 120 can effectively heat the first medium discharged from the first turbine 111.

[0095] According to the operating method of the compressed air energy storage system 100 with a heat exchange subsystem 120 attached to the turbine side according to an embodiment of the present invention, by controlling the flow of the second medium according to the operating state of the heat exchange subsystem 120, it is beneficial to increase the work done by the turbine subsystem 110, increase the power generation of the turbine subsystem 110, and realize additional power generation of the heat exchange subsystem 120, so as to further increase the power generation of the compressed air energy storage system 100 with a heat exchange subsystem 120 attached to the turbine side.

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

[0097] Although the 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 present invention, and that the scope of the present invention is defined by the 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), wherein the turbine subsystem (110) comprises a plurality of first turbines (111), wherein the plurality of first turbines (111) are sequentially connected in series and are used to convert fluid energy of a first medium into mechanical energy; A heat exchange subsystem (120), the heat exchange subsystem (120) comprising a first compressor (121) and a first cooler (122), the first compressor (121) being used to compress a second medium, and the first cooler (122) being connected to an exhaust side of the first compressor (121) and being used to cool the second medium; A first heat exchanger (130), wherein the first heat exchanger (130) comprises a first heat exchange channel and a second heat exchange channel, wherein the first heat exchange channel is connected between the two first turbines (111), and the second heat exchange channel 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 heat exchange subsystem attached to the turbine side according to claim 1, characterized in that: The heat exchange subsystem (120) is provided with a plurality of groups of the first compressors (121) and the first coolers (122), and the first heat exchanger (130) is connected between each group of the first compressors (121) and the first coolers (122).

3. The compressed air energy storage system with a heat exchange subsystem attached to the turbine side according to claim 1, characterized in that: There are a plurality of the first heat exchangers (130), and the first heat exchange channel of each of the first heat exchangers (130) is connected between two adjacently connected first turbines (111).

4. The compressed air energy storage system with a heat exchange subsystem attached to the turbine side according to claim 3, characterized in that: The heat exchange subsystem (120) further includes: a second compressor (123), wherein an air intake side of the second compressor (123) is in communication with the first cooler (122); a second heat exchanger (124), the second heat exchanger (124) having a first circulation channel (1241), one end of the first circulation channel (1241) being in communication with the exhaust side of the second compressor (123), the second heat exchange channel of one of the plurality of first heat exchangers (130) being connected between the second compressor (123) and the first circulation channel (1241) of the second heat exchanger (124); A second turbine (125), the second turbine (125) is connected to the other end of the first flow channel (1241), and the second turbine (125) is used to convert the fluid energy of the second medium into mechanical energy.

5. The compressed air energy storage system with a heat exchange subsystem attached to the turbine side according to claim 4, characterized in that: The second heat exchanger (124) is further provided with a second circulation channel (1242), one end of which is connected to the second turbine (125), so that the second medium flowing through the second turbine (125) can flow into the second circulation channel (1242).

6. The compressed air energy storage system with a heat exchange subsystem attached to the turbine side according to claim 5, characterized in that: The heat exchange subsystem (120) further comprises an air supply channel (126), wherein the air supply channel (126) is used to supply the second medium to the first compressor (121), and the air supply channel (126) is connected to the other end of the second circulation channel (1242).

7. The compressed air energy storage system with a heat exchange subsystem attached to the turbine side according to claim 6, characterized in that: The heat exchange subsystem (120) further comprises a precooler (127), wherein the precooler (127) is disposed in the air supply channel (126), and the precooler (127) is used to cool the second medium in the air supply channel (126).

8. The compressed air energy storage system with a heat exchange subsystem attached to the turbine side according to claim 7, characterized in that: In the air supply path of the air supply channel (126), the connecting position between the second circulation channel (1242) and the air supply channel (126) is arranged upstream of the matching position between the air supply channel (126) and the precooler (127).

9. The compressed air energy storage system with a heat exchange subsystem attached to the turbine side according to claim 5, characterized in that: The compressed air energy storage system also includes a compression subsystem, and the second heat exchanger (124) is also provided with a third circulation channel (1243), the third circulation channel (1243) is connected to the compression subsystem and is used for allowing a third medium in the compression subsystem to pass through, and the third medium is suitable for transferring heat on the compression subsystem side to the second medium in the first circulation channel (1241).

10. The compressed air energy storage system with a heat exchange subsystem attached to the turbine side according to claim 1, characterized in that: The second medium is carbon dioxide.

11. A method for 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 a compressed air energy storage system with a heat exchange subsystem attached to the turbine side according to any one of claims 1 to 10, and the operating method comprises: When the heat exchange subsystem (120) is in the compression stage, the second medium is transported to 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 to the turbine subsystem (110) flows back to the heat exchange subsystem (120), and the heat exchange subsystem (120) generates electricity.

Images