CN-121980733-A - Method for building pressure and energy storage stage model of compressed air energy storage container and simulating method

CN121980733ACN 121980733 ACN121980733 ACN 121980733ACN-121980733-A

Abstract

The invention provides a method for establishing a compression and energy storage stage model of a compressed air energy storage container and simulating the compression and energy storage stage model, and aims to solve the problem that in the prior art, multi-physical field coupling is omitted and dynamic characteristic analysis is insufficient. The method divides the energy storage process into an initial pressure building stage and an energy storage stage, and aims at the initial pressure building stage and the energy storage stage, the energy storage container and the acting container are 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, six assumptions are combined, mathematical models (comprising a gas state equation, a water body control energy equation, a wall control energy equation and the like) of each stage are respectively built based on an energy conservation law and a mass conservation law, and a curve of the pressure and the liquid level change along with time is obtained through simulation calculation, and the mathematical models are compared with experimental results for verification. 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

KOU PANGAO
WU YONGHUA
YAO MINGYU
HUANG XIAOJUN
SONG XIAOHUI
YANG RUI
HAN WEI
ZHAO HANCHEN
LIANG FENGMING

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: 20260505
Application Date: 20251203

Claims (8)

1. The method for establishing and simulating the model of the compressed air energy storage container in the pressure building and energy storage stage 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; step S2, the initial pressure building and energy storage stage is divided into four substeps, wherein the substep 1 fills liquid into the working container 1 by using a pump until the air pressure reaches the same pressure as the energy storage container, the substep 2 fills liquid into the working container 2 until the air pressure reaches the same pressure as the energy storage container after the pressurized gas in the working container 1 is displaced by the liquid in the pump, the substep 4 fills the pressurized gas in the working container 2 into the energy storage container after the pressurized gas in the pump is displaced by the liquid in the pump, the liquid in the working container 1 returns to the reservoir under the atmospheric pressure environment in the substep 3 and the substep 4, and the inflation is completed for 1 time; s3, dividing the energy storage container and the acting container into a control body, and particularly dividing the energy storage container and the acting container 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 uniform temperature distribution in a body, no temperature gradient, (2) keeping the ambient temperature unchanged, (3) keeping the thermal physical characteristics of a container wall material constant, (4) neglecting heat exchange between two container wall controllers, (5) enabling all the processes to be quasi-steady-state processes, and (6) enabling gas in the container to meet an ideal gas state equation, and (7) keeping the temperature of liquid in the container unchanged, wherein the working container is filled with the liquid and then is exhausted into an energy storage container, no energy loss is caused, the liquid in the working container does not influence the operation of a pump in the next step, and (9) enabling the liquid in the working container to flow back to a reservoir under the atmospheric pressure, and neglecting the energy consumption of the part. S5, establishing a mathematical model for each control body in the initial pressure building and energy storage stage based on the law of conservation of energy and the law of conservation of mass, wherein the mathematical model comprises an initial pressure building and energy storage stage energy storage container gas state equation, an initial pressure building and energy storage stage energy storage container wall control energy equation contacted with gas, an initial pressure building and energy storage stage acting container gas state equation, an initial pressure building and energy storage stage acting container water body state equation, an initial pressure building and energy storage stage acting container wall state equation contacted with gas, and an initial pressure building and energy storage stage acting container wall state equation contacted with water body; 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 of claim 1, wherein the initial pressure build-up and energy storage stage in step S5 substep 1 is performed with a rate of change of gas temperature in the power vessel being the sum of a rate of change of gas and wall heat exchange temperature in the power vessel, a rate of change of gas-water heat exchange temperature in the power vessel, a rate of change of air and wall heat exchange temperature, and a rate of change of gas compression process temperature; Wherein, the The air temperature of the steam-water mixing container is, For the contact wall temperature with the gas storage container, To contact the wall temperature with the air in the soda mixing container, The specific heat capacity is fixed for the air of the steam-water mixing container, Is the air quality of the steam-water mixing container, Is the air volume of the soda water mixing container.
3. The method according to claim 2, wherein the wall control energy equation of the initial pressure build-up and energy storage stage in step S5, substep 1, in which the wall energy is in contact with the gas, is satisfied by the change in wall energy being the sum of the heat exchange amount of the wall with the gas in the vessel and the heat exchange amount of the wall with 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.
4. The method according to claim 3, wherein the wall control energy equation of the initial pressure build-up and energy storage stage in step S5, substep 1, in which the wall energy is in contact with the liquid, is satisfied by the change in wall energy being the sum of the heat exchange amount of the wall with the liquid in the container and the heat exchange amount of the wall with the outside atmosphere; 。
5. the method of claim 4, wherein the change rate of the temperature of the gas in the working container and the energy storage container in the initial pressure building and energy storage stage substep 2 is the sum of the change rate of the temperature of the gas in the working container and the temperature of the wall heat exchange, the change rate of the temperature of the gas and the water in the working container, the change rate of the temperature of the air and the wall heat exchange and the change rate of the temperature of the gas compression process; Wherein, the For the air temperature of the air storage container, In order to apply the air temperature of the container, For the contact wall temperature with the gas storage container, To contact the wall temperature with the air in the working vessel, The specific heat capacity is fixed for the air of the air storage container, To fix the specific heat capacity of the working container air, For the air quality of the air storage container, In order to apply the air quality of the container, Is the air volume of the working container.
6. The method according to claim 5, wherein the energy control energy equation of the wall control energy in the energy storage container and the working container in contact with the gas in the initial pressure build-up and energy storage stage substep 2 in the 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.
7. The method according to claim 6, wherein the wall control energy equation of the initial pressure build-up and energy storage stage in step S5, substep 2, of the power vessel in contact with the liquid, is satisfied by the change in wall energy being the sum of the heat exchange amount of the wall with the liquid in the vessel and the heat exchange amount of the wall with the outside atmosphere; 。
8. The method of any one of claims 1 to 7, wherein the gas, liquid, wall control equations in the working vessel in substep 3 are consistent with the control equations in substep 1, the gas, liquid, wall control equations in the working vessel in substep 4 are consistent with the control equations in substep 2, and the gas, wall control equations in the energy storage vessel are consistent with the control equations in substep 2.

Description

Method for building pressure and energy storage stage model of compressed air energy storage container and simulating method Technical Field The embodiment of the invention relates to the technical field of hydraulic compression energy storage, in particular to a method for building a pressure and energy storage 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 for establishing and simulating a model in the pressure building and energy storage stage of a compressed air energy storage container. The embodiment of the invention provides a method for establishing a compression and energy storage stage model of a 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; step S2, the initial pressure building and energy storage stage is divided into four substeps, wherein the substep 1 fills liquid into the working container 1 by using a pump until the air pressure reaches the same pressure as the energy storage container, the substep 2 fills liquid into the working container 2 until the air pressure reaches the same pressure as the energy storage container after the pressurized gas in the working container 1 is displaced by the liquid in the pump, the substep 4 fills the pressurized gas in the working container 2 into the energy storage container after the pressurized gas in the pump is displaced by the liquid in the pump, the liquid in the working container 1 returns to the reservoir under the atmospheric pressure environment in the substep 3 and the substep 4, and the inflation is completed for 1 time; s3, dividing the energy storage container and the acting container into a control body, and particularly dividing the energy storage container and the acting container into a gas control body, a liquid control body, a wall control body contacted with gas an