Compressed air energy storage system and control system thereof

Abstract

The utility model relates to the technical field of compressed air energy storage, in particular to a compressed air energy storage system and a control system thereof, the compressed air energy storage system comprises a first compressor unit, a heat storage and exchange device, a turbine unit, a gas storage and a gas injection regulation and control assembly, the gas outlet end of the gas storage is connected with the turbine unit, the heat storage and exchange device is connected with the first compressor unit and the turbine unit, the gas injection regulation and control assembly is arranged at the gas inlet end of the first compressor unit and comprises a throttling valve and a first heat exchanger, and the output end of the throttling valve is connected with the first heat exchanger. The first heat exchanger output end is connected with the first compressor unit. The technical problem that a first-stage compressor of the compressed air energy storage system is affected by environmental factors is solved.

Description

Technical Field

[0001] The utility model relates to the technical field of compressed air energy storage, and more specifically, to a compressed air energy storage system and its control system. Background Art

[0002] In the current design of compressed air energy storage (CAES) systems, the annual average ambient temperature of the project location is usually used as the base value for the air inlet temperature of the first-stage compressor. This method usually requires assuming a fixed inlet condition. During actual operation, since the ambient temperature varies with seasons and day and night, there are differences between the actual operating conditions and the design conditions. Such differences not only affect the exhaust temperature and pressure during the compression process but also increase the instability and control complexity of the system.

[0003] Specifically, when the actual ambient temperature does not match the design temperature, the inlet state of the first-stage compressor, such as temperature and pressure, will also change, which is directly related to the working efficiency and reliability of the first-stage compressor. For example, at a higher ambient temperature, the air density decreases, and the mass of air in the same volume decreases, resulting in a lower output pressure of the first-stage compressor; conversely, at a lower temperature, the air density increases, which may cause the first-stage compressor to be overloaded. Currently, in order for the first-stage compressor to adapt to different geographical environments and climatic conditions, each system needs to be customized, which not only increases the cost but also reduces the versatility and expandability of the system, thus restricting the development of compressed air energy storage systems. Summary of the Utility Model

[0004] The purpose of the utility model is to provide a compressed air energy storage system and its control system to solve the technical problem that the first-stage compressor of the compressed air energy storage system is affected by environmental factors.

[0005] To achieve the above purpose, the technical solution of the first aspect of the utility model provides a compressed air energy storage system. The compressed air energy storage system includes a first compression unit, a storage heat exchange device, a turbine unit, a gas storage reservoir, and an injection control component. The outlet end of the first compression unit is connected to the gas storage reservoir, the outlet end of the gas storage reservoir is connected to the turbine unit, the storage heat exchange device is respectively connected to the first compression unit and the turbine unit, the injection control component is arranged at the inlet end of the first compression unit, and the injection control component includes a throttle valve and a first heat exchanger. The output end of the throttle valve is connected to the first heat exchanger, and the output end of the first heat exchanger is connected to the first compression unit.

[0006] Further, the first compression unit includes a first compressor and a second compressor. The inlet end of the first compressor is connected to the injection control component, and the outlet end of the first compressor is connected to the second compressor through a second heat exchanger.

[0007] Further, the compressed air energy storage system further includes a second compressor unit, and the second compressor unit includes a third compressor.

[0008] Further, an air outlet end of the second compressor is connected to the third compressor through a third heat exchanger.

[0009] Further, an air outlet end of the third compressor is connected to the gas storage reservoir through a fourth heat exchanger.

[0010] Further, the heat storage and heat exchange device includes a first heat storage and heat exchange assembly, and the first heat storage and heat exchange assembly includes a first storage tank and a second storage tank. The first storage tank is respectively connected to the first compressor unit and the turbine unit, and the second storage tank is respectively connected to the first compressor unit and the turbine unit.

[0011] Further, the heat storage and heat exchange device further includes a second heat storage and heat exchange assembly, and the second heat storage and heat exchange assembly includes a third storage tank and a fourth storage tank. The third storage tank and the fourth storage tank are respectively connected to the gas injection control assembly.

[0012] Further, the third storage tank and the fourth storage tank are also respectively connected to the second compressor unit.

[0013] Further, a fifth heat exchanger is provided between the turbine unit and the gas storage reservoir, and the fifth heat exchanger is connected to the heat storage and heat exchange device.

[0014] The technical solution of the second aspect of the present utility model provides a control system for a compressed air energy storage system, including the compressed air energy storage system described in the technical solution of the first aspect. The control system includes a controller, and the controller is electrically connected between a throttle valve and a first heat exchanger.

[0015] The beneficial effects of the present utility model include:

[0016] 1. For the compressed air energy storage system provided by the present utility model, by arranging a gas injection control assembly at the input end of the first-stage compressor, controlling the air inlet pressure of the first-stage compressor by using a throttle valve, and controlling the air inlet temperature of the first-stage compressor by using a first heat exchanger, thereby controlling the exhaust temperature and pressure of the first-stage compressor, weakening the influence of non-design working conditions of environmental conditions on the compressed air energy storage system, and being beneficial to maintaining the stable operation of each device in the compressed air energy storage system. Description of the Drawings

[0017] To more clearly illustrate the technical solutions of the embodiments of the present utility model, the accompanying drawings required for use in the embodiments of the present utility model will be briefly introduced below. It should be understood that the following accompanying drawings only show some embodiments of the present utility model and should not be regarded as limiting the scope. For those of ordinary skill in the art, without creative efforts, other related accompanying drawings can also be obtained based on these drawings.

[0018] Figure 1 A schematic structural diagram of a compressed air energy storage system provided by an embodiment of the present utility model;

[0019] Figure 2 A schematic structural diagram of an air injection control component provided by an embodiment of the present utility model;

[0020] Figure 3 A schematic structural diagram of a control system of a compressed air energy storage system provided by an embodiment of the present utility model;

[0021] Icons: 100 - First compressor, 110 - Second heat exchanger, 120 - Second compressor, 121 - Third heat exchanger, 200 - Air injection control component, 210 - Throttle valve, 220 - First heat exchanger, 300 - Gas storage, 400 - Turbine unit, 410 - Fifth heat exchanger, 500 - Third compressor, 510 - Fourth heat exchanger, 600 - First storage tank, 610 - Second storage tank, 700 - Third storage tank, 710 - Fourth storage tank. Specific embodiments

[0022] The technical solutions in the embodiments of the present utility model will be described below in conjunction with the accompanying drawings in the embodiments of the present utility model.

[0023] It should be noted that similar reference numerals and letters indicate similar items in the following accompanying drawings. Therefore, once an item is defined in one accompanying drawing, it does not need to be further defined and explained in subsequent accompanying drawings. It should be noted that the orientation or positional relationship indicated by the terms "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the utility model product is usually placed during use. It is only for the convenience of describing the present application 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 should not be construed as a limitation to the present application. In addition, the terms "first", "second", "third", etc. are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance.

[0024] Please refer to Figure 1 、 Figure 2As shown in the figure, the technical solution of the first aspect of the present utility model provides a compressed air energy storage system, which includes a first compressor unit, a heat storage and heat exchange device, a turbine unit 400, a gas storage reservoir 300, and an air injection control component 200. The outlet end of the first compressor unit is connected to the gas storage reservoir 300, the outlet end of the gas storage reservoir 300 is connected to the turbine unit 400, the heat storage and heat exchange device is respectively connected to the first compressor unit and the turbine unit 400, and the air injection control component 200 is arranged at the inlet end of the first compressor unit. The air injection control component 200 includes a throttle valve 210 and a first heat exchanger 220. The output end of the throttle valve 210 is connected to the first heat exchanger 220, and the output end of the first heat exchanger 220 is connected to the first compressor unit. Specifically, the first compressor unit serves as the primary compressor unit of the compressed air energy storage system, which is the first process of the entire compressed air energy storage system. Its main task is to compress ambient air to a certain pressure level. To ensure the efficiency and stability of the compression process, the primary compressor requires stable inlet conditions. The throttle valve 210 is used to adjust the air pressure. By adjusting the opening degree of the throttle valve 210, the air pressure entering the first compressor unit can be controlled to ensure that the first compressor unit operates under an ideal inlet pressure. The first heat exchanger 220 is used to adjust the air temperature. The first heat exchanger 220 can preheat the air to make the air temperature reach the design requirements, thereby reducing the influence of ambient temperature fluctuations on the first compressor unit. The heat storage and heat exchange device includes a first heat storage component and a second heat storage component. The first heat storage component is used to store and exchange heat during the compression process. The heat generated during the compression process can be stored for use during the power generation stage. The second heat storage component supplies heat to the first heat exchanger 220. The gas storage reservoir 300 is used to store the compressed air. When energy is needed, the high-pressure air stored in the gas storage reservoir 300 is released to drive the turbine unit 400 to generate electricity. The turbine unit 400 receives the high-pressure air from the gas storage reservoir 300 and converts its kinetic energy into electrical energy to supply power to the power grid.

[0025] In the compressed air energy storage system provided in this embodiment, by arranging the air injection control component 200 at the input end of the primary compressor, the throttle valve 210 is used to control the air inlet pressure of the primary compressor, and the first heat exchanger 220 is used to control the air inlet temperature of the primary compressor, thereby controlling the exhaust temperature and pressure of the primary compressor, weakening the influence of non-design working conditions of the ambient conditions on the compressed air energy storage system, and being beneficial to maintaining the stable operation of each device in the compressed air energy storage system.

[0026] Preferably, the first compressor unit includes a first compressor 100 and a second compressor 120. The intake end of the first compressor 100 is connected to the gas injection control assembly 200, and the outlet end of the first compressor 100 is connected to the second compressor 120 through a second heat exchanger 110. Specifically, the first compressor 100 is located at the front end of the primary compressor unit, and its intake end is connected to the gas injection control assembly 200. Through the throttle valve 210 and the first heat exchanger 220 in the gas injection control assembly 200, the air pressure and temperature entering the first compressor 100 can be adjusted to ensure that the compression process starts under relatively ideal conditions. The gas cooled by the second heat exchanger 110 enters the second compressor 120 and is continuously compressed to a higher pressure. Multi-stage compression can reduce the load on a single compressor, enabling each stage of the compressor to operate under more ideal conditions. This helps to extend the service life of the compressor and reduce the maintenance frequency. As a high-temperature compressor unit, the first compressor unit works closely with the gas injection control assembly 200, enabling it to better adapt to changes in ambient temperature and maintain the compressor inlet conditions within the design range.

[0027] Preferably, the compressed air energy storage system further includes a second compressor unit. The second compressor unit includes a third compressor 500. The outlet end of the second compressor 120 is connected to the third compressor 500 through a third heat exchanger 121, and the outlet end of the third compressor 500 is connected to the gas storage reservoir 300 through a fourth heat exchanger 510. Specifically, the number of the third compressors 500 can be adjusted according to actual requirements. The third heat exchanger 121 is installed between the outlet end of the second compressor 120 and the intake end of the third compressor 500. Its function is to cool the high-pressure gas discharged from the second compressor 120. By reducing the gas temperature, the energy consumption of the third compressor 500 during the compression process can be reduced, and its working efficiency can be improved. The third compressor 500 receives the high-pressure gas cooled by the third heat exchanger 121 and compresses it in the final stage to reach the high-pressure level required by the gas storage reservoir 300. The outlet end of the third compressor 500 is connected to the gas storage reservoir 300 through a fourth heat exchanger 510.

[0028] Preferably, the heat storage and exchange device includes a first heat storage and exchange component, which includes a first storage tank 600 and a second storage tank 610. The first storage tank 600 is respectively connected to the first compressor unit and the turbine unit 400, and the second storage tank 610 is respectively connected to the first compressor unit and the turbine unit 400. Specifically, the first storage tank 600 is a high-temperature storage tank, and the second storage tank 610 is a low-temperature storage tank. The first storage tank 600 is mainly used to store the heat generated during the compression process. It is connected to the first compressor unit and the turbine unit 400. The air first undergoes preliminary compression by the first compressor unit, generating a large amount of heat, and the heat generated during the compression process is stored in the high-temperature storage tank. The second storage tank 610 is used to store the cooled air or cooling medium. It is also connected to the first compressor unit and the turbine unit 400. During the compression stage, the low-temperature storage tank can help cool the air and reduce the temperature rise during the compression process. During the power generation stage, it can provide a cooling medium to absorb the heat generated by the turbine.

[0029] Preferably, the heat storage and exchange device further includes a second heat storage and exchange component, which includes a third storage tank 700 and a fourth storage tank 710. The third storage tank 700 and the fourth storage tank 710 are respectively connected to the gas injection control component 200, and the third storage tank 700 and the fourth storage tank 710 are also respectively connected to the second compressor unit. Specifically, the third storage tank 700 is a low-temperature tank, and the fourth storage tank 710 is a high-temperature tank. During the compression stage: The air first undergoes pretreatment through the gas injection control component 200 to adjust the pressure and temperature of the air. The pretreated air enters the first compressor 100 for preliminary compression, and the generated heat is stored in the first storage tank 600. The air after preliminary compression is cooled by the second heat exchanger 110 and then enters the second compressor 120 (low-temperature compressor). Before further compression, it is cooled by the second storage tank 610. The air compressed by the second compressor 120 is cooled again by the third heat exchanger 121 and then enters the third compressor 500. The finally compressed air is cooled by the fourth heat exchanger 510 and then stored in the gas storage reservoir 300. During this process, the heat generated by the third compressor 500 is stored in the third storage tank 700 and the fourth storage tank 710. When power generation is required, the heat stored in the third storage tank 700 and the fourth storage tank 710 can be reused to heat the air entering the gas injection control component 200.

[0030] Preferably, a fifth heat exchanger 410 is provided between the turbine unit 400 and the gas storage reservoir 300, and the fifth heat exchanger 410 is connected to the heat storage and exchange device. Specifically, the fifth heat exchanger 410 is used to adjust the temperature of the gas entering the turbine unit 400. During the power generation stage, the high-pressure gas released from the gas storage reservoir 300 passes through the fifth heat exchanger 410, and its temperature is adjusted to adapt to the optimal working conditions of the turbine unit 400.

[0031] Please refer to Figure 3 As shown, the technical solution of the second aspect of the present utility model provides a control system for a compressed air energy storage system, including the compressed air energy storage system described in the technical solution of the first aspect. The control system includes a controller, and the controller is electrically connected to a throttle valve 210 and a first heat exchanger 220; specifically, the first heat exchanger 220 and the throttle valve 210 are configured to be controlled by the electrical connection of the controller, and adjust their working modes according to the instructions issued by the controller to control the air temperature entering the first-stage compressor; for example, the throttle valve 210 adjusts its opening degree through the signal of the controller, thereby controlling the air pressure entering the first-stage compressor. The controller dynamically adjusts the opening degree of the throttle valve 210 according to the current environmental conditions and system requirements to ensure that the compressor operates under the most suitable inlet pressure; the first heat exchanger 220 adjusts its working mode according to the instructions issued by the controller to control the air temperature entering the first-stage compressor. By adjusting the working state of the heat exchanger, it can ensure that the inlet temperature of the compressor is within a suitable range; through the automated control system, the states of the throttle valve 210 and the heat exchanger can be adjusted in real time to ensure that the first-stage compressor operates under the best conditions, thereby improving the stability and reliability of the system. The automated control reduces the necessity of human intervention and reduces the risk of operation errors.

[0032] In addition to the above description, the following points need to be noted:

[0033] (1) The drawings of the embodiments of the present disclosure only relate to the structures involved in the embodiments of the present disclosure, and other structures can refer to the general design;

[0034] (2) The control programs of the controller, valves, compressor units, etc. in the present disclosure are all mature and conventional technologies in the prior art. Those skilled in the art can implement the application of the present utility model according to the principles of the same functions in the prior art. This program part is not the innovation point of the present utility model;

[0035] (3) Without conflict, the embodiments of the present disclosure and the features in the embodiments can be combined with each other to obtain new embodiments.

[0036] The above is only the specific implementation manner of the present utility model, but the protection scope of the present utility model is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present utility model, and all should be covered within the protection scope of the present utility model. Therefore, the protection scope of the present utility model should be subject to the protection scope of the claims.

Claims

1. A compressed air energy storage system, characterized in that: The compressed air energy storage system comprises a first compressor unit, a heat storage and exchange device, a turbine unit (400), an air storage reservoir (300) and an air injection control component (200); the air outlet of the first compressor unit is connected to the air storage reservoir (300), the air outlet of the air storage reservoir (300) is connected to the turbine unit (400), the heat storage and exchange device is connected to the first compressor unit and the turbine unit (400) respectively, the air injection control component (200) is arranged at the air inlet of the first compressor unit, the air injection control component (200) comprises a throttle valve (210) and a first heat exchanger (220), the output end of the throttle valve (210) is connected to the first heat exchanger (220), and the output end of the first heat exchanger (220) is connected to the first compressor unit.

2. The compressed air energy storage system according to claim 1, characterized in that: The first compressor unit comprises a first compressor (100) and a second compressor (120), wherein an air inlet end of the first compressor (100) is connected to a gas injection regulating assembly (200), and an air outlet end of the first compressor (100) is connected to the second compressor (120) via a second heat exchanger (110).

3. The compressed air energy storage system according to claim 2, characterized in that: The compressed air energy storage system further comprises a second compressor group, wherein the second compressor group comprises a third compressor (500).

4. The compressed air energy storage system according to claim 3, characterized in that: The gas outlet end of the second compressor (120) is connected to the third compressor (500) via a third heat exchanger (121).

5. The compressed air energy storage system according to claim 4, characterized in that: The gas outlet end of the third compressor (500) is connected to the gas storage reservoir (300) via a fourth heat exchanger (510).

6. The compressed air energy storage system according to claim 3, characterized in that: The heat storage and exchange device comprises a first heat storage and exchange component, wherein the first heat storage and exchange component comprises a first storage tank (600) and a second storage tank (610), wherein the first storage tank (600) is respectively connected to the first compressor unit and the turbine unit (400), and the second storage tank (610) is respectively connected to the first compressor unit and the turbine unit (400).

7. The compressed air energy storage system according to claim 6, characterized in that: The heat storage and exchange device further comprises a second heat storage and exchange component, wherein the second heat storage and exchange component comprises a third storage tank (700) and a fourth storage tank (710), and the third storage tank (700) and the fourth storage tank (710) are respectively connected to the gas injection control component (200).

8. The compressed air energy storage system according to claim 7, characterized in that: The third storage tank (700) and the fourth storage tank (710) are also respectively connected to the second compressor unit.

9. The compressed air energy storage system according to claim 1, characterized in that: A fifth heat exchanger (410) is provided between the turbine unit (400) and the gas storage reservoir (300), and the fifth heat exchanger (410) is connected to a heat storage and exchange device.

10. A control system for a compressed air energy storage system, characterized in that: A compressed air energy storage system comprising any one of claims 1 to 9, wherein the control system comprises a controller, and the controller is electrically connected to the throttle valve (210) and the first heat exchanger (220).

Images