CN-122021386-A - Method and system for establishing and simulating compression stage model of compressed air energy storage container

CN122021386ACN 122021386 ACN122021386 ACN 122021386ACN-122021386-A

Abstract

The invention provides a method and a system for establishing and simulating a pressure-establishing stage model of a compressed air energy storage container, wherein the method divides an energy storage process into an initial pressure-establishing stage, aims at the initial pressure-establishing stage and a pressure-supplementing stage of an air compressor after multiple times of circulation, divides a steam-water mixing container and a high-pressure air storage container into four parts of a gas control body, a liquid control body, a wall control body contacted with gas and a wall control body contacted with liquid, combines six assumptions, establishes mathematical models (comprising a gas state equation, a water body control energy equation, a wall control energy equation and the like) of each stage based on an energy conservation law and a mass conservation law respectively, obtains a curve of pressure and liquid level change along with time through simulation calculation, and compares the curve with experimental results. The invention comprehensively considers the multi-physical field coupling effect, can accurately reflect the dynamic characteristics of the gas storage container, and provides a reliable theoretical basis for system design and engineering application.

Inventors

FENG HAOYANG
CHANG FENG
KOU PANGAO
LIU WEIJUN
HAN WEI
LIU QI
ZHAO HANCHEN

Assignees

华能陕西吴起发电有限公司
西安热工研究院有限公司
华能陕西发电有限公司

Dates

Publication Date: 20260512
Application Date: 20251217

Claims (10)

1. The method for establishing and simulating the compression stage model of the compressed air energy storage container is characterized by comprising the following steps of: step S1, establishing a mathematical model in a container in the energy storage process of a hydraulic compressed air system according to the pressure-time change relation in the container; S2, filling air into the two containers to a preset air pressure by using the compressor in an initial pressure building stage and a multi-cycle air compressor pressure supplementing stage, and exiting the operation of the compressor; S3, dividing a control body of the steam-water mixing container and the high-pressure gas storage container, and particularly dividing the control body into a gas control body, a liquid control body, a wall control body contacted with gas and a wall control body contacted with liquid; the modeling process of the method comprises the following steps of (1) controlling the uniform distribution of the temperature in a body, no temperature gradient, (2) keeping the ambient temperature unchanged, (3) keeping the thermophysical characteristics of the container wall material constant, (4) neglecting heat exchange between two container wall control bodies, (5) enabling all the processes to be quasi-steady-state, and (6) enabling the gas in the container to meet an ideal gas state equation, and (7) keeping the temperature and the liquid level of the liquid in the container unchanged; S5, establishing a mathematical model for each control body in the initial pressure establishment stage based on an energy conservation law and a mass conservation law, wherein the mathematical model comprises a gas state equation in the initial pressure establishment stage and the air compressor pressure supplementing stage after multiple times of circulation, a water control energy equation in a steam-water mixing container in the initial pressure establishment stage and the air compressor pressure supplementing stage after multiple times of circulation, a wall control energy equation in contact with gas in the initial pressure establishment stage and the air compressor pressure supplementing stage after multiple times of circulation, and a wall control energy equation in contact with liquid in the initial pressure establishment stage and the air compressor pressure supplementing stage after multiple times of circulation; And S6, carrying out simulation calculation and result analysis on the mathematical model established in the step S4 and the step S5 in combination with system parameters to obtain a curve of pressure change along with time, and comparing with an experimental result.
2. The method according to claim 1, wherein the gas state equation in the initial pressure building stage and the air compressor pressure compensating stage after a plurality of cycles in the step S5 is satisfied, wherein the change rate of the gas temperature is the sum of the change rate of the inlet and outlet flowing temperature, the change rate of the temperature of the convective heat transfer with the water body and the change rate of the temperature of the convective heat transfer with the wall; Wherein, the The temperature of the air is set to be the air temperature, In order to achieve a temperature of the incoming gas, For the temperature of the wall of the air contactor, The water temperature of the water body is controlled for the water body, In order to be of air quality, In the form of a volume of air, For the mass flow rate of the air inflow, Is the specific heat capacity of the gas, Is the heat exchange coefficient of the air-water convection, Is the convective heat transfer coefficient of the gas and the wall, Is the area of the water body, Is the area of the wall of the air-contacting device.
3. The method according to claim 2, wherein the wall control energy equation of the gas contact in the initial pressure build-up stage and the air compressor pressure make-up stage after a plurality of cycles in step S5 is satisfied that the change of the wall energy is the sum of the heat exchange amount of the wall and the gas in the container and the heat exchange amount of the wall and the external atmosphere; Wherein, the Is the heat exchange coefficient between the wall surface and the external environment, For the area of the wall exposed to the external environment, Is the external ambient temperature.
4. The method according to claim 3, wherein the wall control energy equation of the initial pressure build-up stage and the air compressor pressure make-up stage after the multiple cycles in step S5 in contact with the liquid is satisfied that the change of the wall energy is the sum of the heat exchange amount of the wall and the liquid in the container and the heat exchange amount of the wall and the external atmosphere; 。
5. The method according to any one of claims 1 to 4, wherein the results of the simulation calculation in step S6 include a curve of the pressure in the steam-water mixing container and the pressure in the high-pressure gas storage container over time during the energy storage.
6. The utility model provides a compressed air energy storage container builds and presses stage model establishment and simulation system which characterized in that includes: The first building module is used for building a mathematical model in the container in the energy storage process of the hydraulic compressed air system according to the pressure-time change relation in the container; The filling module is used for filling air into the two containers to a preset air pressure by using the compressor in an initial pressure building stage and a multi-cycle air compressor pressure supplementing stage, and the compressor is out of operation; The dividing module is used for dividing the control body of the steam-water mixing container and the high-pressure gas storage container, and is particularly divided into a gas control body, a liquid control body, a wall control body contacted with gas and a wall control body contacted with liquid; The modeling process adopts the following assumptions, namely (1) that the temperature in the control body is uniformly distributed and no temperature gradient exists, (2) that the ambient temperature is kept unchanged, (3) that the thermal physical characteristics of the container wall material are constant, (4) that the heat exchange between two container wall control bodies is ignored, (5) that all the processes are quasi-steady-state processes, (6) that the gas in the container meets an ideal gas state equation, and (7) that the temperature and the liquid level of the liquid in the container are kept unchanged; The second building module is used for building a mathematical model for each control body in the initial pressure building stage and the air compressor pressure supplementing stage after multiple times of circulation based on the energy conservation law and the mass conservation law, and comprises a gas state equation in the initial pressure building stage and the air compressor pressure supplementing stage after multiple times of circulation, a water body control energy equation in a steam-water mixing container in the initial pressure building stage and the air compressor pressure supplementing stage after multiple times of circulation, a wall control energy equation in contact with gas in the initial pressure building stage and the air compressor pressure supplementing stage after multiple times of circulation, and a wall control energy equation in contact with liquid in the initial pressure building stage and the air compressor pressure supplementing stage after multiple times of circulation; and the simulation module is used for carrying out simulation calculation and result analysis on the mathematical model established by the assumption module and the second establishment module in combination with the system parameters to obtain a curve of pressure change along with time, and comparing the curve with an experimental result.
7. The system of claim 6, wherein the gas state equation of the initial pressure building stage and the air compressor pressure compensating stage after a plurality of times of circulation is satisfied, and the change rate of the gas temperature is the sum of the change rate of inlet and outlet flowing temperature, the change rate of temperature of convective heat transfer with the water body and the change rate of temperature of convective heat transfer with the wall; Wherein, the The temperature of the air is set to be the air temperature, In order to achieve a temperature of the incoming gas, For the temperature of the wall of the air contactor, The water temperature of the water body is controlled for the water body, In order to be of air quality, In the form of a volume of air, For the mass flow rate of the air inflow, Is the specific heat capacity of the gas, Is the heat exchange coefficient of the air-water convection, Is the convective heat transfer coefficient of the gas and the wall, Is the area of the water body, Is the area of the wall of the air-contacting device.
8. The system of claim 7, wherein the wall control energy of the air compressor in contact with the gas during the initial pressure build-up stage and the air compressor after multiple cycles is such that the change in wall energy is the sum of the heat exchange between the wall and the gas in the container and the heat exchange between the wall and the outside atmosphere; Wherein, the Is the heat exchange coefficient between the wall surface and the external environment, For the area of the wall exposed to the external environment, Is the external ambient temperature.
9. The system of claim 8, wherein the wall control energy of the air compressor in contact with the liquid during the initial pressure build-up stage and the air compressor after multiple cycles is such that the change in wall energy is the sum of the heat exchange between the wall and the liquid in the container and the heat exchange between the wall and the outside atmosphere; 。
10. The system according to any one of claims 6 to 9, wherein the results of the simulation calculation include a profile of the pressure in the steam-water mixing vessel and the pressure in the high pressure gas storage vessel over time during the energy storage process.

Description

Method and system for establishing and simulating compression stage model of compressed air energy storage container Technical Field The embodiment of the invention relates to the technical field of hydraulic compression energy storage, in particular to a method and a system for establishing and simulating a compression stage model of a compressed air energy storage container. Background With the increasing global demand for clean energy, energy storage technology has received great attention as a key means to solve the problems of renewable energy intermittence and volatility. The hydraulic compressed air energy storage technology is used as a novel large-scale energy storage technology, has the advantages of large energy storage capacity, low cost, long service life and the like, and is considered as one of energy storage modes with great development potential. In a hydraulic compressed air energy storage system, an air storage container is one of core components, and the performance of the air storage container directly influences the energy storage efficiency and the stability of the whole system. However, current research in this area faces many challenges. On one hand, the existing gas storage container model only considers the effect of a single physical field, and ignores the strong coupling characteristics among multiple physical fields such as water, gas, machinery, electricity, heat and the like. In the actual operation process, the pressure of the gas in the gas storage container is time-varying, so that the state equation and physical parameters of the gas are affected, and meanwhile, the air can exchange heat with the external environment through the wall of the tank, so that the parameter variation of the air in the container is affected. The traditional models fail to fully reflect the complex correlations, resulting in lower accuracy and reliability of the models. On the other hand, in the energy storage process, parameters such as pressure, liquid level and the like in the gas storage container change rapidly along with time, and the dynamic characteristics of the parameters need to be accurately mastered so as to provide basis for the optimal design and operation control of the system. However, most of the existing researches focus on analysis under steady-state working conditions, and have insufficient simulation and prediction capabilities for dynamic processes. For example, in practical engineering applications, it is difficult for the existing technology to give accurate analysis and solutions on how fast the gas container responds and maintains stable operation when the system load is suddenly changed. In summary, the prior art has shortcomings in the aspects of model establishment and dynamic response characteristic analysis of the hydraulic compressed air energy storage and gas storage device, and is difficult to meet the requirements of high-efficiency and stable operation of the system in actual engineering, and a model establishment and simulation method capable of comprehensively considering multiple physical field coupling, deeply analyzing dynamic characteristics and combining the operation mode of the system is urgently needed. Disclosure of Invention The embodiment of the invention aims at solving at least one of the technical problems existing in the prior art and provides a method and a system for establishing and simulating a compression stage model of a compressed air energy storage container. The embodiment of the invention provides a model building and dynamic characteristic simulation method of a hydraulic compressed air energy storage container, which comprises the following steps: step S1, establishing a mathematical model in a container in the energy storage process of a hydraulic compressed air system according to the pressure-time change relation in the container; S2, filling air into the two containers to a preset air pressure by using the compressor in an initial pressure building stage and a multi-cycle air compressor pressure supplementing stage, and exiting the operation of the compressor; S3, dividing a control body of the steam-water mixing container and the high-pressure gas storage container, and particularly dividing the control body into a gas control body, a liquid control body, a wall control body contacted with gas and a wall control body contacted with liquid; the modeling process of the method comprises the following steps of (1) controlling the uniform distribution of the temperature in a body, no temperature gradient, (2) keeping the ambient temperature unchanged, (3) keeping the thermophysical characteristics of the container wall material constant, (4) neglecting heat exchange between two container wall control bodies, (5) enabling all the processes to be quasi-steady-state, and (6) enabling the gas in the container to meet an ideal gas state equation, and (7) keeping the temperature and the liquid level of the liquid in the container unchang