CN-122021385-A - Method and system for establishing and simulating double power generation stage model of compressed air energy storage container

CN122021385ACN 122021385 ACN122021385 ACN 122021385ACN-122021385-A

Abstract

The invention provides a method and a system for establishing and simulating a model of a double power generation stage of a compressed air energy storage container, which aim at the power generation stage of the joint work of two containers, the method divides a steam-water mixing container and a high-pressure gas 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, based on the energy conservation law and the mass conservation law, the mathematical model (including a gas state equation, a water body control energy equation, a wall control energy equation and the like) of each stage is respectively established by combining six assumptions, and a curve of the pressure and the liquid level changing along with time is obtained through simulation calculation and is compared with an experimental result to verify. The invention comprehensively considers the multi-physical field coupling effect, can accurately reflect the dynamic characteristics of the gas storage container in the discharging process, and provides a reliable theoretical basis for the optimal design and stable operation of the system.

Inventors

KOU PANGAO
LIU WEIJUN
HAN WEI
YANG RUI
ZHAO HANCHEN
WU YONGHUA
SONG XIAOHUI
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: 20260512
Application Date: 20251217

Claims (10)

1. The method for establishing and simulating the double power generation 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 discharging process of a hydraulic compressed air energy storage system according to the pressure-time change relation in the container; s2, in the power generation stage of the joint work of the two containers, air in the high-pressure air storage container is conveyed to the steam-water mixing container through the air pressure control valve, and the air pressure is kept constant until the pressure of the two containers is reduced to a preset value; 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 adopts the following assumptions that (1) the temperature in the control body is uniformly distributed and no temperature gradient exists, (2) the ambient temperature is kept unchanged, (3) the thermal physical characteristics of the container wall material are constant, (4) the heat exchange between two container wall control bodies is ignored, (5) all the processes are quasi-steady-state processes, and (6) the gas in the container meets an ideal gas state equation; S5, establishing a mathematical model for each control body in the two-container co-working power generation stage, wherein the mathematical model comprises a two-container gas control body state equation, a water body control energy equation, a wall control energy equation of a steam-water mixing container power generation stage contacted with gas and a wall control energy equation of a steam-water mixing container power generation stage contacted with liquid; and S6, carrying out simulation calculation and result analysis on the mathematical model established in the step S5 in combination with system parameters to obtain a curve of pressure and liquid level changing along with time, and comparing with an experimental result.
2. The method according to claim 1, wherein the gas control body state equation in the power generation stage of the joint work of the two containers in the step S5 is satisfied, the change rate of the gas temperature in the gas-water mixing container is the sum of the net change rate of the inflow gas temperature, the change rate of the heat exchange temperature of the gas-water mixing container and the change rate of the ideal gas expansion process temperature; Wherein, the For the air temperature of the high-pressure air storage container, The air temperature of the steam-water mixing container is, To contact the wall temperature with the high pressure storage vessel, To contact the wall temperature with the air in the soda mixing container, Is a high-pressure gas storage container the specific heat capacity of the air is fixed, The specific heat capacity is fixed for the air of the steam-water mixing container, For the air quality of the high-pressure air storage container, Is the air quality of the steam-water mixing container, Is the air volume of the steam-water mixing container, Is the mass flow of air flowing into the steam-water mixing container from the high-pressure air storage container.
3. The method according to claim 2, wherein the water body energy control method of the steam-water mixing container in the step S5 is characterized in that the change amount of water energy is the sum of the net change amount of energy of expansion work of compressed air and water outflow, the heat exchange amount of water body and gas and the heat exchange amount of water body and wall: Wherein, the In order to achieve the density of water, Is the specific heat capacity of water, Is the height of the liquid level, and the liquid level is the liquid level, For the temperature of the contact wall with the body of water, Is the heat exchange coefficient of the liquid and the wall surface, Is the area of the wall that is in contact with the liquid.
4. The method according to claim 3, wherein the wall control energy method of the gas contact in the power generation stage of the steam-water mixing vessel in the step S5 is that the change of the wall energy is the sum of the heat exchange amount of the wall and the gas in the vessel 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.
5. The method according to claim 4, wherein the energy control method of the wall in contact with the liquid in the power generation stage of the steam-water mixing container in the step S5 is 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; 。
6. the method according to any one of claims 1 to 5, wherein the results of the simulation calculation in step S6 include curves of the pressure in the soda mixing container, the pressure in the high-pressure gas container, and the liquid level in the soda mixing container over time during the discharging.
7. The utility model provides a compressed air energy storage container dual power generation stage model establishment and simulation system which characterized in that includes: The first establishing module is used for establishing a mathematical model in the container in the discharging process of the hydraulic compressed air energy storage system according to the pressure-time change relation in the container; The conveying module is used for conveying air in the high-pressure air storage container to the steam-water mixing container through the air pressure control valve in the power generation stage of the two containers working together, and maintaining the air pressure constant until the pressure of the two containers is reduced to a preset value; 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 a supposition module, which is used for supposition that (1) the temperature in a control body is uniformly distributed and no temperature gradient exists, supposition that (2) the ambient temperature is kept unchanged, (3) the thermophysical characteristics of the container wall material are constant, (4) the heat exchange between two wall control bodies is ignored, (5) all the processes are quasi-steady-state processes, and supposition that (6) the gas in the container meets an ideal gas state equation; The second building module is used for building a mathematical model for each control body in the power generation stage of the two containers working together, and comprises a two-container gas control body state equation, a water body control energy equation, a wall control energy equation of the power generation stage of the steam-water mixing container contacted with gas, and a wall control energy equation of the power generation stage of the steam-water mixing container contacted with liquid; And the simulation module is used for carrying out simulation calculation and result analysis on the mathematical model established by the second establishment module in combination with the system parameters to obtain a curve of the pressure and liquid level changing along with time, and comparing the curve with an experimental result.
8. The system of claim 7, wherein the gas control body state equation in the combined working power generation stage of the two containers is satisfied, the change rate of the gas temperature in the gas-water mixing container is the sum of the net change rate of the inflow gas temperature, the change rate of the gas-water heat exchange temperature, the change rate of the gas heat exchange temperature with the wall and the change rate of the ideal gas expansion process; Wherein, the For the air temperature of the high-pressure air storage container, The air temperature of the steam-water mixing container is, To contact the wall temperature with the high pressure storage vessel, To contact the wall temperature with the air in the soda mixing container, Is a high-pressure gas storage container the specific heat capacity of the air is fixed, The specific heat capacity is fixed for the air of the steam-water mixing container, For the air quality of the high-pressure air storage container, Is the air quality of the steam-water mixing container, Is the air volume of the steam-water mixing container, Is the mass flow of air flowing into the steam-water mixing container from the high-pressure air storage container.
9. The system of claim 8, wherein the energy control equation of the water body of the steam-water mixing container is that the change amount of the energy of the water body is the sum of the net change amount of the energy of the expansion work of the compressed air and the water outflow, the heat exchange amount of the water body and the gas and the heat exchange amount of the water body and the wall: Wherein, the In order to achieve the density of water, Is the specific heat capacity of water, Is the height of the liquid level, and the liquid level is the liquid level, For the temperature of the contact wall with the body of water, Is the heat exchange coefficient of the liquid and the wall surface, Is the area of the wall that is in contact with the liquid.
10. The system of claim 9, wherein the system further comprises a controller configured to control the controller, The wall control energy equation of the gas-water mixing container in the power generation stage meets the requirement that the change of the wall energy is the sum of the heat exchange quantity of the wall and the gas in the container and the heat exchange quantity 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; The energy control method of the wall control of the steam-water mixing container contacted with the liquid in the power generation stage is that the change of the wall energy is the sum of the heat exchange quantity of the wall and the liquid in the container and the heat exchange quantity of the wall and the external atmosphere; 。

Description

Method and system for establishing and simulating double power generation stage model of compressed air energy storage container Technical Field The embodiment of the invention relates to the technical field of water conservancy compression energy storage, in particular to a method and a system for establishing and simulating a double-power-generation-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 coupling of a thermal force field and a fluid field exists along with the severe temperature change during the compression/expansion of the gas, the pressure of the gas has time-varying characteristics, so that the pressure fluctuation is generated in the container, the coupling of the pressure field and a mechanical field exists, and the dynamic change of parameters such as the gas-liquid contact area, the wall area contacted with water and the like along with the change of the liquid level influences the heat transfer process. The traditional models fail to fully reflect the complex correlations, resulting in lower accuracy and reliability of the models. The prior art has the defects in the aspects of model establishment and dynamic response characteristic analysis of the hydraulic compressed air energy storage and gas storage device, is difficult to meet the requirements on efficient and stable operation of a system in actual engineering, and is urgently needed to be 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. 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 double-power-generation-stage model of a compressed air energy storage container. In a first aspect, an embodiment of the present invention provides a method for building and simulating a dual power generation stage model of a compressed air energy storage container, including the following steps: step S1, establishing a mathematical model in a container in the discharging process of a hydraulic compressed air energy storage system according to the pressure-time change relation in the container; s2, in the power generation stage of the joint work of the two containers, air in the high-pressure air storage container is conveyed to the steam-water mixing container through the air pressure control valve, and the air pressure is kept constant until the pressure of the two containers is reduced to a preset value; 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 adopts the following assumptions that (1) the temperature in the control body is uniformly distributed and no temperature gradient exists, (2) the ambient temperature is kept unchanged, (3) the thermal physical characteristics of the container wall material are constant, (4) the heat exchange between two container wall control bodies is ignored, (5) all the processes are quasi-steady-state processes, and (6) the gas in the container meets an ideal gas state equation; S5, establishing a mathematical model for each control body in the two-container co-working power generation stage, wherein the mathematical model comprises a two-container gas control body state equation, a water body control energy equation, a wall control energy equation of a steam-water mixing container power generation stage contacted with gas and a wall control energy equation of a steam-water mixing container power generation stage contacted with liquid; and S6, carrying out simulation calcul