Compressed air energy storage system utilizing heat supply pipeline to store air and control method

Abstract

The invention discloses a compressed air energy storage system utilizing a heat supply pipeline to store air and a control method, and relates to the technical field of carbon emission reduction, the compressed air energy storage system comprises a control system, a heat supply and air supply system, a compressor and expansion machine system and a heat exchange system, the heat supply and air supply system comprises at least one heat supply boiler and at least one heat exchange station, the compressor and expansion machine system comprises a motor, a compressor, an expansion machine and a generator, the heat exchange system comprises a heat exchanger, a cold storage tank, a heat storage tank and a high-temperature pump, and the control system comprises a frequency converter, a flow meter, a pressure sensor and a temperature sensor. According to the compressed air energy storage system utilizing the heat supply pipeline to store air and the control method, an existing heat supply first-stage pipe network is used as an air storage device, the construction and operation cost of an urban compressed air energy storage power station is remarkably reduced, the flexibility and the response speed of the energy storage system are improved, and the energy storage efficiency is improved. An efficient, economical and environment-friendly energy storage solution is provided for urban users, and the problem of consumption of renewable energy sources is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of carbon emission reduction, and in particular to a compressed air energy storage system and a control method for storing air using a heating pipeline. Background Art

[0002] As the problem of renewable energy consumption becomes increasingly prominent, the volatility of electricity demand is gradually increasing. User-side commercial and industrial energy storage technology is one of the important means to solve the mismatch between energy supply and demand in urban areas. Currently, compressed air energy storage is a promising large-scale power storage technology. It can convert electrical energy into air pressure energy and thermal energy of thermal oil when electricity demand is low, and store them separately. It can also convert the internal energy of the working fluid into electrical energy during peak electricity demand. At present, this technology has been widely used, but the promotion of existing technologies is still limited. One of the more prominent problems is the relatively expensive gas storage facilities.

[0003] The existing compressed air energy storage system gas storage methods can be divided into two types: underground gas storage (such as salt caverns, mines, etc.) and high-pressure gas storage containers (such as steel gas tanks). Among them, the problems of underground gas storage mainly include: high construction costs and difficult construction; strict site selection requirements and many geographical restrictions; long development cycle, requiring a lot of money and time to complete geological surveys and construction. For ground gas storage facilities, such as high-pressure gas storage containers, the main problem is that high-pressure gas tanks need to meet the use requirements of high pressure and frequent filling and discharging, and have high requirements for material strength and safety, and high construction investment and subsequent maintenance costs; in addition, high-pressure gas tanks require a large area to achieve large-scale compressed air storage, and there are certain restrictions on site selection.

[0004] Whether it is an underground gas storage or a high-pressure gas tank, its operation requires a large amount of capital investment. Compressed air energy storage facilities work in a high-temperature and high-pressure environment for a long time. The maintenance costs and safety hazards cannot be ignored. Regular inspections and maintenance are required, which consumes a lot of manpower and material resources.

[0005] Therefore, the low economy and low flexibility of gas storage facilities have become one of the main obstacles to the popularization and large-scale application of compressed air energy storage technology. In order to solve this problem, it is urgent to develop new cost-effective gas storage methods to reduce the construction and operation costs of compressed air energy storage power stations. Summary of the invention

[0006] The purpose of the present invention is to provide a compressed air energy storage system and a control method for storing gas using a heating pipeline, so as to solve the problems faced by existing compressed air energy storage technologies in urban applications, especially the high construction cost and insufficient flexibility of gas storage facilities in the energy storage system. By innovatively utilizing the existing primary heating pipeline network as a gas storage device, the construction and operation costs of urban compressed air energy storage power stations can be significantly reduced, and the flexibility and response speed of the energy storage system can be improved, thereby providing urban users with efficient, economical and environmentally friendly energy storage solutions and promoting the solution to the problem of renewable energy consumption.

[0007] To achieve the above-mentioned object, the present invention provides a compressed air energy storage system using a heating pipeline to store gas, comprising a control system, a heating and gas supply system, a compressor and expander system and a heat exchange system, wherein the heating and gas supply system comprises at least one heating boiler and at least one heat exchange station, the compressor and expander system comprises a motor, a compressor, an expander and a generator, the heat exchange system comprises a heat exchanger, a cold storage tank, a heat storage tank and a high-temperature pump, the heat exchange system, the compressor and expander system and the heating and gas supply system also comprise a plurality of valves, and each system and each system structure is connected by a pipeline; The control system includes a frequency converter, a flow meter, a pressure sensor and a temperature sensor. The control system collects the operating data of each system in real time and monitors and adjusts the working status of each system structure.

[0008] Preferably, the heat exchange station is connected to the hot water pipe of the primary pipeline network through the hot water side inlet valve of the heat exchange station, and is connected to the cold water pipe of the primary pipeline network through the cold water side outlet valve of the heat exchange station; the heating boiler is connected to the cold water pipe of the primary pipeline network through the cold water side inlet valve of the heating boiler, and is connected to the hot water pipe of the primary pipeline network through the hot water side outlet valve of the heating boiler.

[0009] Preferably, the electric motor and the generator are connected to the compressor and the expander respectively, the compressor outlet is provided with a compressor outlet stop valve, the expander inlet stop valve is provided with an expander inlet stop valve, and the expander and the compressor are both connected to the heating boiler through an atmospheric circulation pipeline, and the atmospheric circulation pipeline is provided with a gas storage regulating valve, a gas storage inlet stop valve and a gas storage bypass stop valve.

[0010] Preferably, the heat storage tank and the cold storage tank are connected via an inlet pipeline and an outlet pipeline, the outlet pipeline is provided with a cold storage tank outlet stop valve and a heat storage tank outlet stop valve, and the inlet pipeline is provided with a heat storage tank inlet stop valve and a cold storage tank inlet stop valve; One side pipeline of the variable frequency high temperature pump is connected to the outlet pipeline, and the other side pipeline of the variable frequency high temperature pump is connected to the heat exchanger inlet regulating valve, and a high temperature pump outlet stop valve is arranged between the heat exchanger inlet regulating valve and the variable frequency high temperature pump.

[0011] Preferably, the heat exchanger is connected to the atmospheric circulation pipeline, one side of the heat exchanger is provided with a heat exchanger cold liquid side inlet stop valve and a heat exchanger cold liquid side outlet stop valve connected in parallel, and the other side is provided with a heat exchanger hot liquid side inlet stop valve and a heat exchanger hot liquid side outlet stop valve connected in parallel, and the heat exchanger hot liquid side outlet stop valve and the heat exchanger cold liquid side outlet stop valve are connected in parallel and connected to the inlet pipeline through a pipeline; The inlet stop valve on the cold liquid side of the heat exchanger and the inlet stop valve on the hot liquid side of the heat exchanger are connected in parallel and are connected to the inlet regulating valve of the heat exchanger through a pipeline.

[0012] Preferably, the frequency converter includes a high temperature pump frequency converter, a motor frequency converter and a generator frequency converter which are respectively connected to the variable frequency high temperature pump, the motor and the generator.

[0013] Preferably, the flowmeter includes an air flowmeter connected to the atmospheric circulation pipeline and a thermal oil flowmeter connected to a pipeline on one side of the high-temperature variable frequency pump.

[0014] Preferably, the pressure sensor includes a gas storage pressure sensor connected to the atmosphere circulation pipeline and arranged between the gas storage inlet stop valve and the gas storage bypass stop valve.

[0015] Preferably, the temperature sensors include a heat storage tank temperature sensor, a cold storage tank temperature sensor, a heat exchanger thermal oil cold side temperature sensor and a heat exchanger thermal oil hot side temperature sensor respectively connected to the heat storage tank, the cold storage tank and the heat exchanger, and a heat exchanger air hot side temperature sensor and a heat exchanger air cold side temperature sensor connected to the atmospheric circulation pipeline.

[0016] A control method for a compressed air energy storage system utilizing a heating pipeline to store air comprises the following steps: Step S1, under the control system, adjust the opening of each valve, the speed of the compressor and the expander, and the speed of the high-temperature pump, so that during the energy storage process, the motor and the compressor in the compressor and expander system compress the air to a high-temperature and high-pressure state, the heat exchange system transfers the air heat energy to the heat transfer oil, and stores the heat in the heat storage tank, and the normal temperature and high-pressure air is stored in the heating and gas supply system through the control system; Step S2: During the energy release process, the air in the heating and gas supply system is heated to a high temperature and high pressure state by the heat exchange system, and then the internal energy of the air is converted into electrical energy by the expander and generator in the compressor and expander system.

[0017] Therefore, the present invention adopts the above-mentioned compressed air energy storage system and control method using a heating pipeline to store gas, which has the following beneficial effects: (1) Make full use of existing infrastructure and reduce construction costs: This system combines compressed air energy storage with the heating pipeline system, using the existing primary heating pipeline network as a gas storage facility to reduce the construction cost of compressed air energy storage power stations. At present, the heating pipeline network has covered most of the northern cities in my country. Renovating and upgrading the existing primary heating pipeline network as a compressed air storage device can avoid investing in the construction of new gas storage facilities; at the same time, adding intelligent control equipment can fully improve the operational flexibility of the gas storage device.

[0018] (2) Enhance energy utilization efficiency and achieve energy diversification: This system can coordinate with the heating system to ensure the heating needs of heat users in winter and meet the energy storage needs of urban users during non-heating periods, fully improve the overall utilization rate of the energy system, and achieve diversification of energy supply.

[0019] (3) Promote the widespread application of renewable energy in power systems: This system can combine compressed air energy storage technology with renewable energy power generation. Under the coordinated work of the energy storage control system, monitoring device and control device, it can intelligently control the speed and pressure of the compressor and expander, and has strong adaptability to the intermittent and unstable nature of renewable energy power generation. In addition, this system makes full use of a heat exchange device to achieve the functions of cooling the compressor outlet air during the energy storage stage and heating the expander inlet air during the energy release stage. At the same time, under the action of the control system of the present invention, the amount of heat transfer oil in the heat exchanger is intelligently adjusted, thereby realizing the efficient coupling and decoupling process of pressure energy and thermal energy, and fully improving the adaptability to the volatility of renewable energy (such as wind power generation and solar energy).

[0020] (4) Promote the commercial application of energy storage power stations: This system adopts a lower-cost gas storage method, which improves the economic efficiency of compressed air energy storage technology while reducing the requirements for site selection, promoting the commercial promotion of energy storage power stations. This system uses an efficient and low-cost heat exchange method to accurately match the air heat and the amount of thermal oil to achieve efficient storage and utilization of thermal energy. This intelligent thermal management method improves the overall energy efficiency of the energy storage system and promotes the high coordination and efficiency of the energy storage and release processes. At the same time, this system uses a heat exchange device to achieve intelligent thermal management, significantly reducing the construction and operation costs of compressed air energy storage power stations, and further improving the economic efficiency of the energy storage system.

[0021] (5) Improve the flexibility and reliability of user-side energy storage: This system uses the primary heating pipeline network as a gas storage device, which is suitable for urban construction, meets the diversified energy storage needs of the user side, and promotes power users to participate in grid load regulation and demand response. For users who need a stable power supply (such as hospitals, data centers, etc.), this system can meet the urban power grid accident backup function when the power grid fails or fluctuates, ensuring that key facilities and large-scale activities are not affected by power fluctuations and providing high-quality electricity.

[0022] (6) The benefits of this system are not only reflected in the effective expansion of the functions of traditional heating facilities, but also in its ability to deeply meet the diverse needs of urban users for cost-effective, large-scale energy storage technologies, and promote the formation of an efficient, flexible and low-carbon energy storage and supply platform in urban areas.

[0023] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a structural schematic diagram of an embodiment of a compressed air energy storage system and a control method for storing air using a heating pipeline according to the present invention; Figure numerals: 1, motor; 2, compressor; 3, compressor outlet stop valve; 4, heat exchanger; 5, gas storage regulating valve; 6, gas storage inlet stop valve; 7, gas storage bypass stop valve; 8, expander inlet stop valve; 9, expander; 10, generator; 11, cold storage tank; 12, cold storage tank outlet stop valve; 13, variable frequency high temperature pump; 14, high temperature pump outlet stop valve; 15, heat exchanger inlet regulating valve; 16, heat exchanger cold liquid side inlet stop valve; 17, heat exchanger hot liquid side outlet stop valve; 18, heat storage tank inlet stop valve; 19, heat storage tank; 20, heat storage tank outlet stop valve; 21, heat exchanger hot liquid side inlet stop valve; 22, heat exchanger cold liquid side outlet stop valve; 23, cold storage tank inlet stop valve; 24, air flow meter; 25, heat exchanger air hot side temperature sensor; 26, heat exchanger air cold side temperature sensor; 27. Temperature sensor for cold storage tank; 28. Temperature sensor for heat storage tank; 29. ​​Temperature sensor for cold side of heat transfer oil in heat exchanger; 30. Temperature sensor for hot side of heat transfer oil in heat exchanger; 31. Flow meter for heat transfer oil; 32. Pressure sensor for gas storage; 33. Frequency converter for high temperature pump; 34. Frequency converter for motor; 35. Frequency converter for generator; 36. Control system; 37. Heating boiler; 38. Heat exchange station 1; 39. Heat exchange station 2; 40. Heat exchange station 3; 41. Hot water side outlet valve for heating boiler; 42. Cold water side inlet valve for heating boiler; 43. Hot water side inlet valve for heat exchange station 1; 44. Cold water side outlet valve for heat exchange station 1; 45. Hot water side inlet valve for heat exchange station 2; 46. Cold water side outlet valve for heat exchange station 2; 47. Hot water side inlet valve for heat exchange station 3; 48. Cold water side outlet valve for heat exchange station 3; 49. Hot water pipe for primary network; 50. Cold water pipe for primary network. DETAILED DESCRIPTION

[0025] The technical solution of the present invention is further described below through the accompanying drawings and embodiments.

[0026] Unless otherwise defined, the technical terms or scientific terms used in the present invention should be understood by people with ordinary skills in the field to which the present invention belongs. The words "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0027] Example See also Figure 1 The present invention provides a compressed air energy storage system that uses a heating pipeline to store gas, including a control system 36, a heating and gas supply system, a compressor 2 and an expander 9 system and a heat exchange system. The heating and gas supply system includes at least one heating boiler 37, at least one heat exchange station and various switch valves. The heating and gas supply system refers to the existing primary heating pipeline network in urban areas, which can not only realize the heating function in winter, but also serve as a gas storage device for a compressed air energy storage power station during the idle primary period of the non-heating period. The above-mentioned systems and system structures are connected by pipelines.

[0028] like Figure 1 As shown, the heating and gas supply system demonstrated in this embodiment includes a heating boiler 37 and three heat exchange stations. The specific structure includes the heating boiler 37, heat exchange station one 38, heat exchange station two 39, heat exchange station three 40, a heating boiler hot water side outlet valve 41, a heating boiler cold water side inlet valve 42, a heat exchange station one hot water side inlet valve 43, a heat exchange station one cold water side outlet valve 44, a heat exchange station two hot water side inlet valve 45, a heat exchange station two cold water side outlet valve 46, a heat exchange station three hot water side inlet valve 47, a heat exchange station three cold water side outlet valve 48, a primary network hot water pipe 49, and a primary network cold water pipe 50.

[0029] The basic functions of the heating and gas supply system include heating function and gas storage function. The heating function means that when winter comes, the primary pipeline network of the heating and gas supply system no longer serves as a gas storage facility, but only provides the function of transporting hot water. The gas storage function means that when the heating function is not in effect, the primary pipeline network of the heating and gas supply system serves as a gas storage facility, providing the function of a gas storage facility for the compressed air energy storage system. When the heating function is started, all valves are closed, the outlet valve 41 of the hot water side of the heating boiler, the inlet valve 42 of the cold water side of the heating boiler, the inlet valve 43 of the hot water side of the heat exchange station 1, the outlet valve 44 of the cold water side of the heat exchange station 1, the inlet valve 45 of the hot water side of the heat exchange station 2, the outlet valve 46 of the cold water side of the heat exchange station 2, the inlet valve 47 of the hot water side of the heat exchange station 3 and the outlet valve 48 of the cold water side of the heat exchange station 3 are opened, and the heating boiler 37, the heat exchange station 1 38, the heat exchange station 2 39 and the heat exchange station 3 40 are started. Hot water flows out from the heating boiler 37 along the hot water pipe 49 of the primary pipeline network to heat exchange station one 38, heat exchange station two 39 and heat exchange station three 40; cold water flows from heat exchange station one 38, heat exchange station two 39 and heat exchange station three 40 along the cold water pipe 50 of the primary pipeline network back to the heating boiler 37.

[0030] The compressor 2 and expander 9 system includes a motor 1, a compressor 2, an expander 9, a generator 10, and various switch valves. The compressor 2 and expander 9 system is the core part of the compressed air energy storage system and is responsible for the compression and expansion of air. The compressor 2 system compresses the air to a high-pressure state during the energy storage stage, and the expander 9 system is responsible for expanding the stored high-pressure air during the energy release stage, releasing the stored energy and driving the generator 10 to generate electricity.

[0031] like Figure 1 As shown, in this embodiment, the compressor 2 and expander 9 system includes an electric motor 1, a compressor 2, a compressor outlet stop valve 3, a gas storage regulating valve 5, a gas storage inlet stop valve 6, a gas storage bypass stop valve 7, an expander inlet stop valve 8, an expander 9 and a generator 10.

[0032] The basic functions of the compressor 2 and expander 9 system include the compressor 2 function and the expander 9 function. The compressor 2 function means that the compressor 2 works in the energy storage stage to compress the air in the atmosphere to a high temperature and high pressure state. The expander 9 function means that the expander 9 works in the energy release stage, the high temperature and high pressure air expands, and the internal energy of the air is converted into electrical energy. When the compressor 2 function is started, all valves are closed, the compressor outlet stop valve 3, the gas storage regulating valve 5, the gas storage inlet stop valve 6 and the gas storage bypass stop valve 7 are opened, the gas supply function of the heating and gas supply system is opened, and the motor 1 and the compressor 2 are started. During energy storage, the motor 1 drives the compressor 2 to work, and the air is compressed from the atmosphere to a high temperature and high pressure state. The high temperature and high pressure air enters the heat exchanger 4 through the compressor outlet stop valve 3 and is cooled to a normal temperature state, and enters the heating and gas supply system through the gas storage regulating valve 5, the gas storage inlet stop valve 6 and the gas storage bypass stop valve 7. When the expander 9 function is started, all valves are closed, the gas storage bypass stop valve 7, the gas storage inlet stop valve 6, the gas storage regulating valve 5 and the expander inlet stop valve 8 are opened, the gas supply function of the heating and gas supply system is turned on, and the expander 9 and the generator 10 are started. When releasing energy, high-pressure air is released from the heating and gas supply system, enters the heat exchanger 4 through the gas storage bypass stop valve 7, the gas storage inlet stop valve 6 and the gas storage regulating valve 5, is heated to a high temperature state, passes through the expander inlet stop valve 8, and the air internal energy in the expander 9 is converted into the mechanical energy of the expander 9, and is converted into electrical energy through the generator 10, and the low-pressure air is discharged to the atmosphere.

[0033] The heat exchange system includes a heat exchanger 4, a cold storage tank 11, a heat storage tank 19, a variable frequency high temperature pump 13 and various switch valves, and the heat storage medium is heat transfer oil. The heat exchange system is mainly used to separate and store the heat of the air at the outlet of the compressor 2 during energy storage, and to provide heat for the inlet of the expander 9 during energy release. In the energy storage stage, the normal temperature heat transfer oil flows out of the cold storage tank 11, enters the variable frequency high temperature pump 13 for pressure increase, and then enters the heat exchanger 4. The high temperature and high pressure air transfers heat to the heat transfer oil in the heat exchanger 4, so that after the heat transfer oil is heated, the high temperature heat transfer oil enters the heat storage tank 19 to store the heat, realizing the separation of heat energy and pressure energy. In the energy release stage, the high temperature heat transfer oil flows out of the heat storage tank 19 and enters the variable frequency high temperature pump 13 for pressure increase. After the pressure increase, the high temperature heat transfer oil enters the heat exchanger 4 to transfer heat to the normal temperature high pressure air, and the cooled heat transfer oil returns to the cold storage tank 11. This improves the efficiency of the expander 9, ensures the effective use of energy, and reduces energy loss.

[0034] like Figure 1As shown, in this embodiment, the heat exchange system specifically includes a heat exchanger 4, a cold storage tank 11, a cold storage tank outlet stop valve 12, a variable frequency high temperature pump 13, a high temperature pump outlet stop valve 14, a heat exchanger inlet regulating valve 15, a heat exchanger cold liquid side inlet stop valve 16, a heat exchanger hot liquid side outlet stop valve 17, a heat storage tank inlet stop valve 18, a heat storage tank 19, a heat storage tank outlet stop valve 20, a heat exchanger hot liquid side inlet stop valve 21, a heat exchanger cold liquid side outlet stop valve 22 and a cold storage tank inlet stop valve 23. The heat storage medium in the heat exchange system is heat transfer oil.

[0035] The main purpose of the heat exchange system is to separate and store the heat of the air at the outlet of the compressor 2 during energy storage, and to provide heat for the inlet of the expander 9 during energy release. The specific implementation process is that when storing energy, all valves of the heat exchange system remain closed, the cold storage tank outlet stop valve 12, the high temperature pump outlet stop valve 14, the heat exchanger inlet regulating valve 15, the heat exchanger cold liquid side inlet stop valve 16, the heat exchanger hot liquid side outlet stop valve 17 and the heat storage tank inlet stop valve 18 are opened, and the variable frequency high temperature pump 13 is started. Normal temperature heat transfer oil flows out of the cold storage tank 11, passes through the cold storage tank outlet stop valve 12, enters the variable frequency high temperature pump 13 for pressure increase, passes through the high temperature pump outlet stop valve 14, the heat exchanger inlet regulating valve 15 and the heat exchanger cold liquid side inlet stop valve 16, and enters the cooling liquid inlet side of the heat exchanger. The high temperature air transfers heat to the heat transfer oil in the heat exchanger, causing the heat transfer oil to heat up, and the high temperature heat transfer oil passes through the heat exchanger hot liquid side outlet stop valve 17 and the heat storage tank inlet stop valve 18 and enters the heat storage tank 19. When releasing energy, all valves of the heat exchange system remain closed, and the heat storage tank outlet stop valve 20, the high temperature pump outlet stop valve 14, the heat exchanger inlet regulating valve 15, the heat exchanger hot liquid side inlet stop valve 21, the heat exchanger cold liquid side outlet stop valve 22 and the cold storage tank inlet stop valve 23 are opened to start the variable frequency high temperature pump 13. The high temperature heat transfer oil flows out of the heat storage tank 19, enters the variable frequency high temperature pump 13 through the heat storage tank outlet stop valve 20, and the boosted high temperature heat transfer oil passes through the high temperature pump outlet stop valve 14, the heat exchanger inlet regulating valve 15 and the heat exchanger hot liquid side inlet stop valve 21, and enters the high temperature liquid inlet side of the heat exchanger 4. After transferring heat to the air, the cooled heat transfer oil passes through the heat exchanger cold liquid side outlet stop valve 22 and the cold storage tank inlet stop valve 23 and returns to the cold storage tank 11.

[0036] The control system 36 includes a frequency converter, a flow meter, a pressure sensor and a temperature sensor. The control system 36 collects the operating data of each system in real time, monitors and adjusts the working status of each system structure. The control system 36 collects the operating data of each component in real time, thereby accurately adjusting the operating conditions of the compressor 2 and the expander 9, thereby optimizing the flow, pressure, temperature and other parameters during the energy storage and release process. The control system 36 also includes functions such as gas storage container pressure regulation and gas storage temperature regulation, which can automatically adjust according to energy demand and system operating conditions to achieve optimal energy storage and release efficiency.

[0037] like Figure 1 As shown, in this embodiment, the control system 36 specifically includes a variable frequency high temperature pump inverter 33, a motor inverter 34, a generator inverter 35, an air flow meter 24, a heat exchanger air hot side temperature sensor 25, a heat exchanger air cold side temperature sensor 26, a cold storage tank temperature sensor 27, a heat storage tank temperature sensor 28, a heat exchanger thermal oil cold side temperature sensor 29, a heat exchanger thermal oil hot side temperature sensor 30, a thermal oil flow meter 31, a gas storage pressure sensor 32 and a control system 36.

[0038] The functions of the control system 36 include adjusting the speed of the motor 1, adjusting the speed of the generator 10, adjusting the flow rate of the heat transfer oil and adjusting the gas storage pressure. The purpose of adjusting the speed of the motor 1 is to maintain and adjust the speed of the motor 1 according to the input power of different frequencies, so that the compressor 2 can meet the energy supply of various renewable energy sources and maintain a high working efficiency. The implementation process is that the control system 36 measures the frequency of the input power and the performance curve of the compressor 2, adjusts the output frequency of the frequency converter, and thus adjusts the speed of the motor 1 and the compressor 2. The purpose of adjusting the speed of the generator 10 is to adjust the speed of the expander 9 according to the gas storage pressure in the heating and gas supply system so that it works in the best efficiency state, and adjusts the frequency of the power provided by the generator 10 to meet the grid frequency requirements. The implementation process is that the control system 36 adjusts the frequency of the generator frequency converter 35 and the speed of the expander 9 according to the pressure displayed by the gas storage pressure sensor 32 and the performance curve of the expander 9 so that it works in the best performance condition, and at the same time ensures that the output power frequency meets the grid requirements.

[0039] The heat transfer oil flow adjustment function means that the present invention can adjust the flow of heat transfer oil in real time according to the outlet temperature of the compressor 2 and the air storage temperature, thereby reducing the heat loss of energy storage. The specific implementation process is that when storing energy, the opening of the heat exchanger inlet regulating valve 15 and the speed of the variable frequency high temperature pump 13 are adjusted according to the air temperature displayed by the heat exchanger air cold side temperature sensor 26 and the heat exchanger air hot side temperature sensor 25. For example, during energy storage, when the air temperature displayed by the heat exchanger air cold side temperature sensor 26 is too high, the opening of the heat exchanger inlet regulating valve 15 is increased, and the frequency of the variable frequency high temperature pump inverter 33 and the speed of the variable frequency high temperature pump 13 are adjusted, thereby increasing the flow rate of the heat transfer oil flowing out of the cold storage tank 11 into the heat exchanger 4 and reducing the air temperature; when the air temperature displayed by the heat exchanger air cold side temperature sensor 26 is too low, the opening of the heat exchanger inlet regulating valve 15 is reduced, and the frequency of the variable frequency high temperature pump inverter 33 and the speed of the variable frequency high temperature pump 13 are adjusted, thereby reducing the flow rate of the heat transfer oil flowing out of the cold storage tank 11 into the heat exchanger 4 and increasing the air temperature. During energy release, when the air temperature displayed by the heat exchanger air hot side temperature sensor 25 is too low, the opening of the heat exchanger inlet regulating valve 15 is increased, and the frequency of the variable frequency high temperature pump inverter 33 and the speed of the variable frequency high temperature pump 13 are adjusted, so that the flow rate of the heat transfer oil flowing out of the heat storage tank 19 into the heat exchanger 4 is increased, and the air temperature entering the expander 9 is increased; when the air temperature displayed by the heat exchanger air hot side temperature sensor 25 is too high, the opening of the heat exchanger inlet regulating valve 15 is reduced, and the frequency of the variable frequency high temperature pump inverter 33 and the speed of the variable frequency high temperature pump 13 are adjusted, so that the flow rate of the heat transfer oil flowing out of the heat storage tank 19 into the heat exchanger 4 is reduced, and the air temperature entering the expander 9 is reduced.

[0040] The control method of the compressed air energy storage system using the heating pipeline to store gas comprises the following steps: Step S1, under the control system 36, adjust the opening of each valve, the speed of the compressor 2 and the expander 9, and the speed of the variable frequency high temperature pump 13, so that during the energy storage process, the motor 1 and the compressor 2 in the compressor 2 and the expander 9 system compress the air to a high temperature and high pressure state, the heat exchange system transfers the air heat energy to the heat transfer oil, and stores the heat in the heat storage tank 19, and the normal temperature and high pressure air is stored in the heating and gas supply system through the control system 36; Step S2, during the energy release process, the air in the heating and gas supply system is heated to a high temperature and high pressure state by the heat exchange system, and then the internal energy of the air is converted into electrical energy by the expander 9 and the generator 10 in the compressor 2 and expander 9 system.

[0041] Therefore, the present invention adopts the above-mentioned compressed air energy storage system and control method that utilizes heating pipelines to store gas, and utilizes the existing primary heating pipeline network as a gas storage device, which significantly reduces the construction and operation costs of urban compressed air energy storage power stations, and improves the flexibility and response speed of the energy storage system, providing urban users with efficient, economical and environmentally friendly energy storage solutions, and promoting the solution to the problem of renewable energy consumption.

[0042] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. A compressed air energy storage system utilizing a heating pipeline to store air, characterized in that: It includes a control system, a heating and gas supply system, a compressor and expander system and a heat exchange system. The heating and gas supply system includes at least one heating boiler and at least one heat exchange station. The compressor and expander system includes a motor, a compressor, an expander and a generator. The heat exchange system includes a heat exchanger, a cold storage tank, a heat storage tank and a high-temperature pump. The heat exchange system, the compressor and expander system and the heating and gas supply system also include a plurality of valves, and each system and each system structure is connected by a pipeline; The control system includes a frequency converter, a flow meter, a pressure sensor and a temperature sensor. The control system collects the operating data of each system in real time and monitors and adjusts the working status of each system structure.

2. A compressed air energy storage system utilizing heating pipeline gas storage according to claim 1, characterized in that: The heat exchange station is connected to the hot water pipe of the primary pipeline network through the hot water side inlet valve of the heat exchange station, and is connected to the cold water pipe of the primary pipeline network through the cold water side outlet valve of the heat exchange station; the heating boiler is connected to the cold water pipe of the primary pipeline network through the cold water side inlet valve of the heating boiler, and is connected to the hot water pipe of the primary pipeline network through the hot water side outlet valve of the heating boiler.

3. A compressed air energy storage system utilizing heating pipeline gas storage according to claim 2, characterized in that: The electric motor and the generator are connected to the compressor and the expander respectively. The compressor outlet is provided with a compressor outlet stop valve, and the expander inlet is provided with an expander inlet stop valve. The expander and the compressor are both connected to the heating boiler through an atmospheric circulation pipeline. The atmospheric circulation pipeline is provided with a gas storage regulating valve, a gas storage inlet stop valve and a gas storage bypass stop valve.

4. A compressed air energy storage system utilizing heating pipeline gas storage according to claim 3, characterized in that: The heat storage tank and the cold storage tank are connected through an inlet pipeline and an outlet pipeline. The outlet pipeline is provided with a cold storage tank outlet stop valve and a heat storage tank outlet stop valve, and the inlet pipeline is provided with a heat storage tank inlet stop valve and a cold storage tank inlet stop valve; One side pipeline of the variable frequency high temperature pump is connected to the outlet pipeline, and the other side pipeline of the variable frequency high temperature pump is connected to the heat exchanger inlet regulating valve, and a high temperature pump outlet stop valve is arranged between the heat exchanger inlet regulating valve and the variable frequency high temperature pump.

5. A compressed air energy storage system utilizing heating pipeline gas storage according to claim 4, characterized in that: The heat exchanger is connected to the atmospheric circulation pipeline. One side of the heat exchanger is provided with a heat exchanger cold liquid side inlet stop valve and a heat exchanger cold liquid side outlet stop valve connected in parallel, and the other side is provided with a heat exchanger hot liquid side inlet stop valve and a heat exchanger hot liquid side outlet stop valve connected in parallel. The heat exchanger hot liquid side outlet stop valve and the heat exchanger cold liquid side outlet stop valve are connected in parallel and connected to the inlet pipeline through a pipeline. The inlet stop valve on the cold liquid side of the heat exchanger and the inlet stop valve on the hot liquid side of the heat exchanger are connected in parallel and are connected to the inlet regulating valve of the heat exchanger through a pipeline.

6. A compressed air energy storage system utilizing heating pipeline gas storage according to claim 5, characterized in that: The frequency converter includes a high temperature pump frequency converter, a motor frequency converter and a generator frequency converter which are respectively connected to the variable frequency high temperature pump, the motor and the generator.

7. A compressed air energy storage system utilizing heating pipeline gas storage according to claim 6, characterized in that: The flow meter includes an air flow meter connected to the atmospheric circulation pipeline and a heat transfer oil flow meter connected to the pipeline on one side of the high-temperature variable frequency pump.

8. A compressed air energy storage system utilizing heating pipeline gas storage according to claim 7, characterized in that: The pressure sensor comprises a gas storage pressure sensor connected to the atmosphere circulation pipeline and arranged between the gas storage inlet stop valve and the gas storage bypass stop valve.

9. A compressed air energy storage system utilizing heating pipeline gas storage according to claim 8, characterized in that: The temperature sensors include a heat storage tank temperature sensor, a cold storage tank temperature sensor, a heat exchanger thermal oil cold side temperature sensor and a heat exchanger thermal oil hot side temperature sensor respectively connected to the heat storage tank, the cold storage tank and the heat exchanger, and a heat exchanger air hot side temperature sensor and a heat exchanger air cold side temperature sensor connected to the atmospheric circulation pipeline.

10. A control method for a compressed air energy storage system utilizing a heating pipeline to store gas according to any one of claims 1 to 9, characterized in that: The following steps are involved: Step S1, under the control system, adjust the opening of each valve, the speed of the compressor and the expander, and the speed of the high-temperature pump, so that during the energy storage process, the motor and the compressor in the compressor and expander system compress the air to a high-temperature and high-pressure state, the heat exchange system transfers the air heat energy to the heat transfer oil, and stores the heat in the heat storage tank, and the normal temperature and high-pressure air is stored in the heating and gas supply system through the control system; Step S2: During the energy release process, the air in the heating and gas supply system is heated to a high temperature and high pressure state by the heat exchange system, and then the internal energy of the air is converted into electrical energy by the expander and generator in the compressor and expander system.

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