Compressed air energy storage system

Abstract

A compressed air energy storage system, comprising an air storage apparatus (10), a compressor unit (20), an electric motor (30), a circulating heat storage assembly (40), and an organic Rankine cycle power generation assembly (50). The compressor unit (20) comprises at least two compressors (21) and an interstage cooler (22) arranged between each two adjacent compressors (21). The electric motor (30) is connected to a compressor (21). The circulating heat storage assembly (40) comprises a low-temperature heat storage tank (41) and a high-temperature heat storage tank (42). At least one interstage cooler (22) is connected between the low-temperature heat storage tank (41) and the high-temperature heat storage tank (42). The organic Rankine cycle power generation assembly (50) is connected between the high-temperature heat storage tank (42) and the low-temperature heat storage tank (41), and is used to receive a high-temperature working medium outputted by the high-temperature heat storage tank (42) and generate electricity using heat provided by the high-temperature working medium.

Description

Compressed air energy storage system TECHNICAL FIELD

[0001] The present application relates to the technical field of power system energy storage, in particular to a compressed air energy storage system. BACKGROUND

[0002] With the continuous expansion of new energy power generation capacity and the construction of new power systems, the demand for power system energy storage is increasingly urgent. Existing energy storage technologies include pumped storage, compressed air energy storage, electrochemical energy storage, flywheel energy storage, superconducting magnetic energy storage, etc. Compressed air energy storage has the characteristics of large energy storage scale, long energy storage time, high conversion efficiency, long service life, safe and stable operation, etc., and can realize energy storage services such as power peak regulation, frequency regulation, phase regulation, backup, and emergency, which meets the demand for large-scale and long-time energy storage of power systems, and is one of the effective ways to solve the problem of renewable energy consumption and an important carrier for building new power systems.

[0003] In related technologies, the adiabatic compressed air energy storage technology stores a large amount of compression heat generated during the compression process, and in the energy release process, the stored compression heat is used to heat the compressed air, which then drives the turbine to generate electricity, thereby improving the electric conversion efficiency. However, after each charging and discharging process, part of the unused high-temperature heat storage medium remains in the system. In the compression and expansion process of an ideal gas, the heat absorption and heat release are equal in theory, but in the actual process, there is also an entropy increase heat in the electric-thermal conversion during air compression, and there is a heat exchange end difference in the heat exchanger. Therefore, after the turbine generates all the electricity, part of the heat is not utilized and is stored in the high-temperature heat storage tank in the form of high-temperature heat storage medium (such as high-temperature hot water, molten salt or high-temperature working medium such as heat conducting oil).

[0004] However, the current treatment method is to return the part of the high-temperature heat storage medium to the low-temperature heat tank after cooling with circulating cooling water for storage, which is used for inter-stage cooling in the next air compression process. This method not only does not recover heat, but also consumes a large amount of electric energy and cooling water, resulting in a large waste and reducing the system efficiency.

[0005] SUMMARY

[0006] Therefore, it is necessary to overcome the defects of the prior art and provide a compressed air energy storage system to solve the problem of how to improve the system efficiency.

[0007] The present application provides a compressed air energy storage system, comprising:

[0008] The gas storage device is connected with the input pipeline and the output pipeline;

[0009] The compressor unit comprises at least two compressors arranged in the input pipeline and an inter-stage cooler arranged between adjacent two compressors;

[0010] a motor connected with the compressor and used to drive the compressor to compress air so that the air enters the air storage device through the input pipeline;

[0011] a circulating heat storage assembly including a low-temperature heat storage tank and a high-temperature heat storage tank, at least one inter-stage cooler connected between the low-temperature heat storage tank and the high-temperature heat storage tank, the low-temperature heat storage tank used to supply low-temperature working medium to the inter-stage cooler so that the low-temperature working medium absorbs heat in the inter-stage cooler to become high-temperature working medium, and the high-temperature heat storage tank used to receive the high-temperature working medium output by the inter-stage cooler.

[0012] an organic Rankine cycle power generation assembly connected between the high-temperature heat storage tank and the low-temperature heat storage tank, the organic Rankine cycle power generation assembly used to receive the high-temperature working medium output by the high-temperature heat storage tank and generate power under the heat provided by the high-temperature working medium, and capable of returning low-temperature working medium to the low-temperature heat storage tank.

[0013] In one embodiment, the output pipeline is provided with at least two air turbines and a first generator, the output pipeline is provided with an air heater upstream of the air turbines, one end of the air heater is connected with the high-temperature heat storage tank, and the other end of the air heater is connected with the low-temperature heat storage tank, the high-temperature heat storage tank is used to input high-temperature working medium to the air heater, so that the air heater heats the compressed air output by the air storage device to the air turbines, and the air turbines are used to receive the compressed air and drive the first generator to generate power.

[0014] In one embodiment, the organic Rankine cycle power generation assembly includes, in sequence, an evaporator, an expander, a condenser and a working medium pump, the expander is connected with a second generator, the working medium pump is used to pump the liquid working medium output by the condenser to the evaporator, the evaporator is used to heat the liquid working medium pumped by the working medium pump under the action of the high-temperature working medium, so that the liquid working medium is gasified into gaseous working medium, the expander is used to drive the second generator to generate power under the pushing of the gaseous working medium, and the condenser is used to condense the gaseous working medium output by the expander into liquid working medium.

[0015] In one embodiment, the output pipeline is provided with at least two air turbines and a first generator, the output pipeline is provided with an electric heater upstream of the air turbines, the electric heater is electrically connected with the second generator, the second generator is used to supply power to the electric heater, so that the electric heater heats the compressed air output by the air storage device to the air turbines, and the air turbines are used to receive the compressed air and drive the first generator to generate power.

[0016] In one of the embodiments, all the electric heaters are connected in parallel to the second generator.

[0017] In one of the embodiments, the compressed air energy storage system further comprises a first liquid pump and a second liquid pump, the first liquid pump is arranged at the output end of the low-temperature heat storage tank, and the second liquid pump is arranged at the output end of the high-temperature heat storage tank.

[0018] In one of the embodiments, the compressed air energy storage system further comprises a third valve arranged between the second liquid pump and the evaporator of the organic Rankine cycle power generation assembly.

[0019] In one of the embodiments, the expander is a centripetal turbine expander, and the working medium pump is a variable frequency pump.

[0020] In one of the embodiments, the compressed air energy storage system further comprises a cooler arranged in the input pipeline and located between the gas storage device and the compressor closest to the gas storage device.

[0021] In one of the embodiments, the input pipeline and the output pipeline are respectively provided with a first valve and a second valve, the first valve is located at the input end of the gas storage device, and the second valve is located at the output end of the gas storage device.

[0022] The compressed air energy storage system of the present application is connected with the organic Rankine cycle power generation assembly between the low-temperature heat storage tank and the high-temperature heat storage tank, the organic Rankine cycle power generation assembly recovers and utilizes the heat energy of the high-temperature working medium in the high-temperature heat storage tank to generate power, thereby realizing the recovery and utilization of the surplus heat in the system, avoiding the waste of the surplus heat of the high-temperature working medium, and because the high-temperature working medium is converted into low-temperature working medium after passing through the organic Rankine cycle power generation assembly and flows back to the low-temperature heat storage tank, the high-temperature working medium does not need to be cooled by using cooling water in the traditional technology, therefore, the compressed air energy storage system of the present application can reduce energy waste, increase power generation, and effectively improve the system efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0023] The accompanying drawings, which form a part of the present application, are intended to provide further understanding of the present application, and the illustrative embodiments of the present application and their description serve the purpose of explaining the present application. The accompanying drawings should not be construed as an inappropriate limitation to the present application.

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the accompanying drawings needed to be used in the embodiment description will be briefly introduced. Obviously, the accompanying drawings in the following description are only some embodiments of the present application, and other accompanying drawings can be obtained by those skilled in the art without any creative effort.

[0025] Fig. 1 is a schematic diagram of a compressed air energy storage system according to an embodiment of the present application.

[0026] Fig. 2 is a schematic diagram of a compressed air energy storage system according to another embodiment of the present application.

[0027] Fig. 3 is a schematic diagram of a compressed air energy storage system according to still another embodiment of the present application.

[0028] Fig. 4 is a schematic diagram of a compressed air energy storage system according to yet another embodiment of the present application.

[0029] Brief Description of the Drawings: 10, air storage device; 10a, input pipeline; 10b, output pipeline; 10c, first valve; 10d, second valve; 20, compressor unit; 21, compressor; 22, inter-stage cooler; 30, electric motor; 40, circulating heat storage assembly; 41, low-temperature heat storage tank; 41a, first liquid pump; 42, high-temperature heat storage tank; 42a, second liquid pump; 42b, third valve; 50, organic Rankine cycle power generation assembly; 51, evaporator; 52, expander; 53, condenser; 54, working fluid pump; 55, second generator; 60, air turbine; 60a, air heater; 60b, electric heater; 70, first generator; 80, cooler. DETAILED DESCRIPTION

[0030] In order to make the above objectives, features and advantages of the present application more apparent, specific embodiments of the present application will be described in detail below with reference to the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. However, the present application can be practiced in a number of ways beyond the specific embodiments described and claimed herein. It is therefore intended that the present application not be limited in scope to the specific embodiments disclosed but rather that the scope of the present application be measured by the broadest permissible interpretation of the claims.

[0031] Referring to Fig. 1, a compressed air energy storage system according to an embodiment of the present application includes an air storage device 10, a compressor unit 20, an electric motor 30, a circulating heat storage assembly 40 and an organic Rankine cycle power generation assembly 50. In the compressed air energy storage system, these assemblies are connected by pipelines to realize the transfer of medium. For the convenience of understanding, the pipeline located at the input end of the air storage device 10 is referred to as "input pipeline 10a", and the pipeline located at the output end of the air storage device 10 is referred to as "output pipeline 10b". In this way, the air storage device 10 is connected with the input pipeline 10a and the output pipeline 10b. Understandably, the air storage device 10 can be a tank or a box, which is not limited herein.

[0032] The compressor set 20 comprises at least two compressors 21 arranged in the input pipeline 10a and an inter-stage cooler 22 arranged between two adjacent compressors 21. The motor 30 is connected with the compressors 21, and the motor 30 is used to drive the compressors 21 to compress air so that the air enters the air storage device 10 through the input pipeline 10a. It should be noted that the compressed air compressed by the compressors 21 and entering the air storage device 10 can be in a liquid state or in a gaseous state, which is not limited here.

[0033] The number of compressors 21 can be two, or three or more. The compressors 21 are arranged in sequence along the input pipeline 10a to form a multi-stage compression structure, so as to compress the air in multiple stages, so that the pressure of the air transported in the input pipeline 10a gradually increases, and finally the compressed air is transported to the air storage device 10 for storage, so that the energy is stored in the form of compressed air.

[0034] Since the inter-stage cooler 22 is arranged between two adjacent compressors 21, the heat energy generated during the compression of the air by the compressors 21 is collected by the inter-stage cooler 22, and the heat energy is transferred in the form of heating the working medium.

[0035] Specifically, the circulating heat storage assembly 40 comprises a low-temperature heat storage tank 41 and a high-temperature heat storage tank 42. At least one inter-stage cooler 22 is connected between the low-temperature heat storage tank 41 and the high-temperature heat storage tank 42, that is, in the pipeline, at least one inter-stage cooler 22 is connected between the low-temperature heat storage tank 41 and the high-temperature heat storage tank 42, so that the working medium circulating between the low-temperature heat storage tank 41 and the high-temperature heat storage tank 42 passes through the at least one inter-stage cooler 22, so that the at least one inter-stage cooler 22 can use the heat energy generated by the compressed air to heat the working medium, so that the low-temperature working medium output by the low-temperature heat storage tank 41 is heated to high-temperature working medium after flowing through the at least one inter-stage cooler 22, and the high-temperature working medium flows into the high-temperature heat storage tank 42 to realize the recovery of the surplus heat energy of the system.

[0036] It should be noted that the plurality of inter-stage coolers 22 can be one connected between the low-temperature heat storage tank 41 and the high-temperature heat storage tank 42, or all connected between the low-temperature heat storage tank 41 and the high-temperature heat storage tank 42.

[0037] With reference to Figs. 1-3, the compressors 21 in the compressor set 20 are numbered sequentially in the direction of air flow into the air storage device 10, for example, as the first compressor 21, the second compressor 21, and the third compressor 21. In some embodiments, such as the compressed air energy storage system shown in Fig. 1, only the inter-stage cooler 22 between the first compressor 21 and the second compressor 21 is connected between the low temperature thermal reservoir 41 and the high temperature thermal reservoir 42. In some embodiments, such as the compressed air energy storage system shown in Fig. 2, only the inter-stage cooler 22 between the second compressor 21 and the third compressor 21 is connected between the low temperature thermal reservoir 41 and the high temperature thermal reservoir 42. In some embodiments, all of the inter-stage coolers 22 are connected between the low temperature thermal reservoir 41 and the high temperature thermal reservoir 42. Specifically, with reference to Fig. 3, the inter-stage coolers 22 between any two compressors 21 are connected between the low temperature thermal reservoir 41 and the high temperature thermal reservoir 42, which improves the recovery rate of the waste heat generated by the compressed air.

[0038] As can be appreciated, the low temperature thermal reservoir 41 is configured to circulate a low temperature working fluid to the inter-stage coolers 22, so that the low temperature working fluid absorbs heat from the inter-stage coolers 22 to become a high temperature working fluid, and the high temperature thermal reservoir 42 is configured to receive the high temperature working fluid output by the inter-stage coolers 22. In this way, the heat generated during the compression of air is recovered during the process in which the low temperature working fluid becomes the high temperature working fluid by passing through the inter-stage coolers 22, and the energy in the form of the high temperature working fluid is stored in the high temperature thermal reservoir 42 as the high temperature working fluid enters the high temperature thermal reservoir 42.

[0039] In the embodiments of the present application, the energy of the high temperature working fluid output from the high temperature thermal reservoir 42 is converted into electrical energy by the organic Rankine cycle power generation assembly 50, thereby achieving the recovery and utilization of the waste heat of the system. Specifically, the organic Rankine cycle power generation assembly 50 is connected between the high temperature thermal reservoir 42 and the low temperature thermal reservoir 41. The organic Rankine cycle power generation assembly 50 is configured to receive the high temperature working fluid output by the high temperature thermal reservoir 42 and generate electricity under the heat provided by the high temperature working fluid. As can be appreciated, the temperature of the high temperature working fluid will decrease to become a low temperature working fluid after the heat of the high temperature working fluid is converted into electrical energy by the organic Rankine cycle power generation assembly 50. Since the organic Rankine cycle power generation assembly 50 is connected to the low temperature thermal reservoir 41, the low temperature working fluid can flow back to the low temperature thermal reservoir 41 after the high temperature working fluid becomes the low temperature working fluid. In this way, the low temperature working fluid continues to circulate through the inter-stage coolers 22 to continuously collect the heat generated during the compression of air by the compressors 21.

[0040] Since the compressed air energy storage system of the present application is provided with the organic Rankine cycle power generation assembly 50 connected between the low-temperature heat storage tank 41 and the high-temperature heat storage tank 42, the organic Rankine cycle power generation assembly 50 recovers and utilizes the heat energy of the high-temperature working medium in the high-temperature heat storage tank 42 to generate power, thereby realizing the recovery and utilization of the excess heat in the system and avoiding the waste of the excess heat of the high-temperature working medium. Moreover, since the high-temperature working medium is converted into low-temperature working medium after passing through the organic Rankine cycle power generation assembly 50 and flows back to the low-temperature heat storage tank 41, it is not necessary to use cooling water to cool the high-temperature working medium as in the traditional technology. Therefore, the compressed air energy storage system of the present application can reduce energy waste, increase power generation, and effectively improve the system efficiency.

[0041] In some embodiments, the output pipeline 10b is provided with at least two air turbines 60 and a first generator 70. The output pipeline 10b is provided with an air heater 60a upstream of the air turbines 60, one end of the air heater 60a is connected to the high-temperature heat storage tank 42, and the other end is connected to the low-temperature heat storage tank 41. The high-temperature heat storage tank 42 is used to input high-temperature working medium to the air heater 60a, so that the air heater 60a heats the compressed air of the air storage device 10 to the air turbines 60. In this embodiment, the air turbines 60 are used to receive compressed air and drive the first generator 70 to generate power, so that the energy of the compressed air of the compressor 21 is output in the form of electric energy through the first generator 70. In this way, the compressed air energy storage system can realize the storage and release of electric energy, so as to facilitate the coordination of the power grid. For example, when the power grid has excess electric energy, in order to avoid waste of electric energy, the electric energy can be used to drive the motor 30 to rotate, so that the motor 30 drives the compressor set 20 to compress air, so that the energy is stored in the air storage device 10 in the form of compressed air. Correspondingly, when the power grid has insufficient electric energy, the compressed air stored in the air storage device 10 can be released to the output pipeline 10b, so that the air turbines 60 in the output pipeline 10b convert the energy of the compressed air into power to drive the first generator 70 to generate power, so as to supplement the electric energy of the power grid, thereby coordinating the power grid through the energy storage and release process of the compressed air energy storage system.

[0042] Referring to FIG. 1 again, the organic Rankine cycle power generation assembly 50 comprises, in sequence, an evaporator 51, an expander 52, a condenser 53 and a working medium pump 54. The inlet of the evaporator 51 is connected to the outlet of the working medium pump 54, the outlet of the evaporator 51 is connected to the inlet of the expander 52, the outlet of the expander 52 is connected to the inlet of the condenser 53, and the outlet of the condenser 53 is connected to the inlet of the working medium pump 54. The evaporator 51 is connected to the high-temperature heat storage tank 42 and the low-temperature heat storage tank 41, so that the high-temperature working medium output by the high-temperature heat storage tank 42 is used to heat the evaporator 51 to evaporate the organic working medium flowing through the evaporator 51. In this embodiment, the expander 52 is connected to a second generator 55, the working medium pump 54 is used to pump the liquid working medium output by the condenser 53 to the evaporator 51, the evaporator 51 is used to heat the liquid working medium pumped by the working medium pump 54 under the action of the high-temperature working medium, so that the liquid working medium is gasified into gaseous working medium, the expander 52 is used to drive the second generator 55 to generate power under the driving of the gaseous working medium, and the condenser 53 is used to condense the gaseous working medium flowing out of the expander 52 into liquid working medium. As can be seen, the organic Rankine cycle power generation assembly 50 absorbs the heat of the high-temperature working medium of the high-temperature heat storage tank 42 by the liquid working medium to become gaseous working medium, so as to drive the expander 52 to drive the second generator 55 to generate power by the gaseous working medium, thereby realizing the conversion of the heat energy of the high-temperature working medium output by the high-temperature heat storage tank 42 into electric energy, realizing the utilization of the heat of the high-temperature working medium, and improving the power generation efficiency.

[0043] By using the organic Rankine cycle power generation assembly 50 to recycle the waste heat, the power generation capacity can be improved by 4.5%, and the system efficiency can be improved by 3.2% by using the compressed air energy storage system of the present application. In addition, the organic Rankine cycle assembly has the characteristics of simplicity, flexibility and compact structure, so that the compressed air energy storage system has high adjustability.

[0044] For example, in some embodiments, the high-temperature working medium in the high-temperature heat storage tank 42 is not limited to being heated by the air heater 60a located upstream of the air turbine 60 to improve the air expansion efficiency. The high-temperature working medium in the high-temperature heat storage tank 42 can also be used to heat the compressed air output from the air storage device 10 after being converted into electric energy by the organic Rankine cycle power generation assembly 50 to improve the air expansion efficiency.

[0045] Specifically, referring to FIG. 4, the output pipeline 10b is provided with at least two air turbines 60 and a first generator 70. The output pipeline 10b is provided with an electric heater 60b upstream of the air turbine 60. The electric heater 60b is electrically connected to the second generator 55. The second generator 55 is used to supply power to the electric heater 60b, so that the electric heater 60b heats the compressed air output from the air storage device 10 to the air turbine 60. The air turbine 60 is used to receive the compressed air and drive the first generator 70 to generate power.

[0046] In this embodiment, the second generator 55 is used to output electric energy to power the electric heater 60b, so that the electric heater 60b heats the compressed air from the air storage device 10 to the air turbine 60. This mode has good controllability, and the working state of the second generator 55 is easy to control, which is beneficial to realize the electrical control of the compressed air energy storage system to release compressed air to convert into electric energy, so that the compressed air energy storage system is simple and flexible.

[0047] Further, all the electric heaters 60b are connected in parallel to the second generator 55, so as to use the same voltage output by the second generator 55 to power each electric heater 60b, so as to fully exert the heating performance of the electric heater 60b, thereby improving the expansion efficiency of the compressed air, and making the air turbine 60 drive the first generator 70 to generate electricity more efficiently.

[0048] In the above embodiment, the expander 52 includes but is not limited to a centrifugal turbine expander 52. The working fluid pump 54 includes but is not limited to a variable frequency pump.

[0049] In some embodiments, the compressed air energy storage system further comprises a first liquid pump 41a and a second liquid pump 42a. The first liquid pump 41a is arranged at the output end of the low-temperature heat storage tank 41, so that the first liquid pump 41a can be used to pump the low-temperature working fluid in the low-temperature heat storage tank 41 to the inter-stage cooler 22, and make the high-temperature working fluid passing through the inter-stage cooler 22 flow into the high-temperature heat storage tank 42. The second liquid pump 42a is arranged at the output end of the high-temperature heat storage tank 42, so that the second liquid pump 42a can be used to pump the high-temperature working fluid in the high-temperature heat storage tank 42, so that the high-temperature working fluid transmits heat to the heat-using position. For example, the second liquid pump 42a pumps the high-temperature working fluid in the high-temperature heat storage tank 42 to flow through the organic Rankine cycle power generation assembly 50 to realize the conversion of heat energy into electric energy; for another example, in the embodiment in which the output pipeline 10b corresponds to the upstream of the air turbine 60 and is provided with the air heater 60a, the second liquid pump 42a pumps the high-temperature working fluid in the high-temperature heat storage tank 42 to flow through the air heater 60a to heat the compressed air flowing through the air heater 60a, so as to accelerate the expansion efficiency of the compressed air, thereby improving the working efficiency of the air turbine 60 to drive the first generator 70 to generate electricity.

[0050] It should be noted that the compressed air energy storage system further comprises some valves for controlling the opening and closing of the pipelines. For example, in some embodiments, the input pipeline 10a and the output pipeline 10b are respectively provided with a first valve 10c and a second valve 10d, the first valve 10c is located at the input end of the gas storage device 10, and the second valve 10d is located at the output end of the gas storage device 10. In this way, the opening and closing of the input end of the gas storage device 10 can be controlled by using the first valve 10c, and the opening and closing of the output end of the gas storage device 10 can be controlled by using the second valve 10d. For example, during the compressed air energy storage process, the first valve 10c is opened and the second valve 10d is closed, so that the compressed gas can be filled into the gas storage device 10 for storage. When the compressed air is released, the first valve 10c is closed and the second valve 10d is opened, so that the compressed gas can only be output from the output pipeline 10b to drive the air turbine 60 on the output pipeline 10b to work, thereby driving the first generator 70 to generate electricity under the driving of the air turbine 60.

[0051] In some embodiments, the compressed air energy storage system further comprises a third valve 42b, which is arranged between the second liquid pump 42a and the evaporator 51 of the organic Rankine cycle power assembly 50, so as to adjust the timing of the high-temperature heat storage tank 42 outputting the high-temperature working medium to the evaporator 51, so as to control the timing of the second generator 55 generating electricity. For example, during the process of releasing compressed air of the compressed air energy storage system, in order to speed up the expansion efficiency of the compressed air, the third valve 42b can be closed, so that the high-temperature working medium pumped by the second liquid pump 42a is all used to heat the compressed air in the output pipeline 10b through the air heater 60a. For another example, when the heat required by the air heater 60a is far less than the heat energy that can be provided by the high-temperature working medium pumped by the second liquid pump 42a, in order to reduce the heat energy loss of the high-temperature working medium, the third valve 42b can be opened, so that part of the high-temperature working medium will convert the heat into electric energy through the organic Rankine cycle power assembly 50, thereby improving the system efficiency. Of course, in some embodiments, when the gas storage device 10 does not output high-pressure air through the output pipeline 10b, the third valve 42b can also be opened, so that the high-temperature heat storage tank 42 can provide high-temperature working medium to the organic Rankine cycle power assembly 50 to output electric energy.

[0052] In some embodiments, the compressed air energy storage system further comprises a cooler 80, which is arranged in the input pipeline 10a and located between the gas storage device 10 and the closest compressor 21 to the gas storage device 10, so as to condense the compressed air into liquid state, thereby facilitating storage in the gas storage device 10.

[0053] It should be noted that the inlet of the compressor set 20 is in communication with the atmosphere, and the outlet of the air turbine 60 at the end of the output pipeline 10b is in communication with the atmosphere. During the energy storage process of the compressed air energy storage system, the atmosphere is sucked into the compressor set 20 and compressed to form compressed air, and finally the compressed air is stored in the gas storage device 10. During the process of releasing the energy of the compressed air in the compressed air energy storage system, the compressed air flows through the air turbine 60 through the output pipeline 10b, and the expansion of the compressed air in the air turbine 60 drives the first generator 70 to generate electricity, and the expanded air is discharged from the outlet of the air turbine 60 at the end of the output pipeline 10b into the atmosphere. In some embodiments, a filter is arranged at the inlet of the compressor set 20 for air intake to ensure that clean air enters the compressed air energy storage system, thereby ensuring the service life of each element in the compressed air energy storage system. A gas-water separator is arranged between the gas storage device 10 and the air heater 60a, and a gas-water separator is arranged between the inlet of the compressor 21 and the inter-stage cooler 22.

[0054] Any combination of the technical features in the above embodiments can be combined. In order to make the description simple, not all possible combinations of the technical features in the above embodiments are described, but as long as the combination of the technical features does not exist contradictory, it should be considered as the scope of the description.

[0055] The above embodiments only express several embodiments of the present application, and the description is more specific and detailed, but it should not be understood as limiting the scope of the patent of the present application. It should be noted that for ordinary skilled persons in the art, without departing from the inventive concept of the present application, a number of modifications and improvements can be made, which are within the scope of protection of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

[0056] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the purpose of facilitating the description of the present application and simplifying the description, and do 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 limiting the present application.

[0057] In addition, the terms "first", "second", etc. are used only for descriptive purposes and are not to be construed as indicating or implying relative importance or an ordered ranking of the indicated technical features. Thus, a feature defined with "first", "second" can explicitly or implicitly comprise at least one of the features. In the description of the present application, the meaning of "a plurality" is at least two, for example two, three, etc., unless otherwise explicitly specified and limited.

[0058] In the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting", "fixing" and the like should be understood broadly, for example, can be fixedly connected, or can be detachably connected, or can be integrated; can be mechanically connected, or can be electrically connected; can be directly connected, or can be indirectly connected through an intermediate medium; can be the internal communication of two elements or the interaction relationship between two elements, unless otherwise explicitly limited. For those skilled in the art, the specific meaning of the above-mentioned terms in the present application can be understood according to the specific circumstances.

[0059] In the present application, unless otherwise explicitly specified and limited, the first feature is "on" or "under" the second feature, which can be direct contact between the first and second features, or indirect contact between the first and second features through an intermediate medium. Moreover, the first feature "above", "above" and "above" the second feature can be directly above or obliquely above the first feature, or only indicate that the horizontal height of the first feature is higher than that of the second feature. The first feature "below", "below" and "below" the second feature can be directly below or obliquely below the first feature, or only indicate that the horizontal height of the first feature is less than that of the second feature.

Claims

1. A compressed air energy storage system, characterized in that, The application relates to a kind of air storage device and air turbine power generation system, comprising: Air storage device, connected with input pipeline and output pipeline; Compressor unit, comprising at least two compressors arranged in the input pipeline and inter-stage cooler arranged between adjacent two compressors; Motor, connected with the compressor, and used to drive the compressor to compress air, so that air enters the air storage device through the input pipeline; Circulating heat storage assembly, comprising low-temperature heat storage tank and high-temperature heat storage tank, at least one inter-stage cooler is connected between the low-temperature heat storage tank and the high-temperature heat storage tank, the low-temperature heat storage tank is used to supply low-temperature working medium to the inter-stage cooler, so that the low-temperature working medium absorbs heat in the inter-stage cooler to become high-temperature working medium, and the high-temperature heat storage tank is used to receive high-temperature working medium output by the inter-stage cooler; Organic Rankine cycle power generation assembly, connected between the high-temperature heat storage tank and the low-temperature heat storage tank, used to receive high-temperature working medium output by the high-temperature heat storage tank and generate power under the heat provided by the high-temperature working medium, and capable of returning low-temperature working medium to the low-temperature heat storage tank.

2. The compressed air energy storage system of claim 1, wherein, The output pipeline is provided with at least two air turbines and a first generator, the output pipeline is provided with an air heater upstream of the air turbine, one end of the air heater is connected with the high-temperature heat storage tank, and the other end is connected with the low-temperature heat storage tank, the high-temperature heat storage tank is used to input high-temperature working medium to the air heater, so that the air heater heats compressed air output by the air storage device to the air turbine, and the air turbine is used to receive the compressed air and drive the first generator to generate power.

3. The compressed air energy storage system of claim 1, wherein, The organic Rankine cycle power generation assembly comprises an evaporator, an expander, a condenser and a working medium pump connected in sequence, the expander is connected with a second generator, the working medium pump is used to pump liquid working medium output by the condenser to the evaporator, the evaporator is used to heat liquid working medium pumped by the working medium pump under the action of high-temperature working medium, so that the liquid working medium is gasified into gaseous working medium, the expander is used to drive the second generator to generate power under the push of gaseous working medium, and the condenser is used to condense gaseous working medium flowing out of the expander into liquid working medium.

4. The compressed air energy storage system of claim 3, wherein, The output pipeline is provided with at least two air turbines and a first generator, the output pipeline is provided with an electric heater upstream of the air turbine, the electric heater is electrically connected with the second generator, the second generator is used to supply power to the electric heater, so that the electric heater heats compressed air output by the air storage device to the air turbine, and the air turbine is used to receive the compressed air and drive the first generator to generate power.

5. The compressed air energy storage system of claim 4, wherein, All the electric heaters are connected in parallel with the second generator.

6. The compressed air energy storage system of claim 3 or 4, wherein, Further comprising a first liquid pump and a second liquid pump, the first liquid pump is arranged at the output end of the low-temperature heat storage tank, and the second liquid pump is arranged at the output end of the high-temperature heat storage tank.

7. The compressed air energy storage system of claim 6, wherein, Further comprising a third valve, arranged between the second liquid pump and the evaporator of the organic Rankine cycle power generation assembly.

8. The compressed air energy storage system of claim 3 or 4, wherein, The expander is a centripetal turbine expander, and the working medium pump is a variable frequency pump.

9. The compressed air energy storage system of claim 1, wherein, The system further comprises a cooler arranged in the input pipeline between the gas storage device and the closest compressor to the gas storage device.

10. The compressed air energy storage system of claim 1, wherein, The input pipeline and the output pipeline are respectively provided with a first valve and a second valve, the first valve is arranged at the input end of the gas storage device, and the second valve is arranged at the output end of the gas storage device.

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