CN-121981014-A - Compressed air energy storage gas storage reservoir capacity and inflation and deflation rate determining method and system based on thermodynamic response differential decomposition

CN121981014ACN 121981014 ACN121981014 ACN 121981014ACN-121981014-A

Abstract

The invention provides a method and a system for determining the storage capacity and the charging and discharging rate of a compressed air energy storage gas storage based on thermodynamic response differential decomposition, comprising the steps of establishing a gas storage thermodynamic response differential model, and obtaining the maximum Yong which can be stored in the gas storage and the maximum pressure reached by air in the gas storage based on the gas storage thermodynamic response differential model; and drawing the contour lines of the maximum Yong and the maximum pressure on a two-dimensional plane of the reservoir capacity-the inflation and deflation rate, and determining the feasible design values of the reservoir capacity and the inflation and deflation rate which simultaneously meet Yong storage and pressure constraint by utilizing the intersection points of the two contour lines to finish the optimal design of the compressed air energy storage and gas storage. The technical scheme of the invention provides an efficient and accurate theoretical tool for the design of the CAES gas storage.

Inventors

ZHANG GUOHUA
WANG HONGJIN
Hua Dongjie
XIONG FENG
Tu Fubin
WANG YONGYU

Assignees

中国地质大学（武汉）

Dates

Publication Date: 20260505
Application Date: 20260212

Claims (8)

1. The method for determining the storage capacity and the charging and discharging rate of the compressed air energy storage warehouse based on thermodynamic response difference decomposition is characterized by comprising the following steps of: Establishing a differential model of the thermodynamic response of the gas storage, and obtaining the maximum Yong which can be stored in the gas storage and the maximum pressure reached by the air in the gas storage based on the differential model of the thermodynamic response of the gas storage; and respectively drawing the contour lines of the maximum Yong and the maximum pressure on a two-dimensional plane of the reservoir capacity-the inflation and deflation rate, and determining the reservoir capacity and inflation and deflation rate feasible design values which simultaneously meet Yong storage and pressure constraint by utilizing the intersection points of the two contour lines to finish the optimal design of the compressed air energy storage and gas storage.
2. The method of claim 1, wherein the method of modeling the differential thermodynamic response of the gas reservoir comprises: Based on a mass conservation equation, an energy conservation equation and a gas state equation, a control equation set for describing air temperature, pressure, quality and surrounding rock temperature change of the gas storage in the process of charging and discharging circulation is established; Discretizing the time and space, solving the control equation set by adopting a differential method to obtain dynamic response of air pressure, temperature, Yong and surrounding rock temperature field in the air reservoir changing along with time under the input condition of preset reservoir capacity and air charging and discharging speed, and completing construction of a thermodynamic response differential model of the air reservoir.
3. The method according to claim 2, wherein the construction method of the mass conservation equation, the energy conservation equation, and the gas state equation comprises: constructing a mass conservation equation based on the air release mass flow and the air filling mass flow in the air storage; constructing a hole wall heat flow equation based on the hole wall area, the average heat exchange coefficient of the hole wall and air, the air temperature in the air storage and the air wall temperature of the air storage; obtaining air specific enthalpy based on the specific internal energy, the air pressure in the air storage, the air volume in the air storage and the air quality in the air storage; constructing an energy conservation equation based on the mass, the charge and discharge rate, the air specific internal energy, the cavity wall heat flow equation and the air specific enthalpy of the air in the air storage; and constructing a gas state equation based on the air pressure in the gas storage, the volume of the gas storage, the air ratio and the gas constant and the air temperature in the gas storage.
4. A method according to claim 3, wherein the method of constructing a system of control equations comprises: based on the conservation of mass equation, the specific enthalpy of air and the heat flow equation of the hole wall, a differential form of the conservation of energy equation and the gas state equation is obtained; Based on the differential form of the energy conservation equation and the gas state equation, obtaining a change relation of temperature and pressure in the gas storage; Constructing a temperature change relation caused by heat conduction in the rock based on the density of the rock, the specific heat capacity of the rock, the heat conductivity coefficient of the rock, the radius of the wall surface of the gas storage, the average heat exchange coefficient of the wall surface of the gas storage, the air temperature in the gas storage, the rock temperature at the wall surface of the gas storage and the environmental temperature; and based on a temperature change relational expression caused by heat conduction in the rock mass, completing the construction of a control equation set.
5. The method of claim 2, wherein the method of obtaining the maximum Yong and maximum pressure comprises: based on the specific gas storage site, obtaining relevant thermodynamic parameters; constructing a design parameter space based on the related thermodynamic parameters; based on the thermodynamic response differential model of the gas storage, combinations of different storage capacities and inflation and deflation rates in the design parameter space are traversed, and a complete inflation and deflation cycle is simulated, so that the maximum Yong and the maximum pressure are obtained.
6. The method of claim 5, wherein the associated thermodynamic parameters include a cavity radius, a rock mass density, a rock mass thermal conductivity, a rock mass specific heat, a heat transfer coefficient, an air-gas constant, an air-specific heat ratio, an initial air-to-rock mass temperature, a cavity initial pressure, a maximum internal pressure design value, and a maximum Yong design value.
7. A compressed air energy storage reservoir capacity and charge-discharge rate determination system based on thermodynamic response differential decomposition for implementing the method of any one of claims 1-6, comprising: the differential model construction module is used for establishing a differential model of the thermodynamic response of the gas storage, and obtaining the maximum Yong which can be stored in the gas storage and the maximum pressure reached by the air in the gas storage based on the differential model of the thermodynamic response of the gas storage; And the feasible design value acquisition module is used for respectively drawing the maximum contour lines Yong and the maximum pressure contour lines on a two-dimensional plane of the reservoir capacity-the inflation and deflation rate, determining the reservoir capacity and the feasible design value of the inflation and deflation rate which simultaneously meet Yong storage and pressure constraint by utilizing the intersection points of the two contour lines, and completing the optimal design of the compressed air energy storage and gas storage.
8. The system of claim 7, wherein the differential model building module comprises: The control equation set construction unit is used for constructing a control equation set for describing air temperature, pressure, quality and surrounding rock temperature change of the gas storage in the process of charging and discharging circulation based on a mass conservation equation, an energy conservation equation and a gas state equation; The differential model construction unit is used for carrying out discretization on time and space, solving the control equation set by adopting a differential method, obtaining dynamic response of air pressure, temperature and Yong in the air storage and temperature field of surrounding rock along with time change under the input condition of preset storage capacity and air charging and discharging speed, and completing construction of the thermodynamic response differential model of the air storage.

Description

Compressed air energy storage gas storage reservoir capacity and inflation and deflation rate determining method and system based on thermodynamic response differential decomposition Technical Field The invention belongs to the technical field of Compressed AIR ENERGY Storage (CAES), and particularly relates to a method and a system for determining the Storage capacity and the charging and discharging rate of a Compressed air Storage based on thermodynamic response difference decomposition. Background Compressed Air Energy Storage (CAES) is a large-scale and long-term energy storage technology, and has important significance for stabilizing new energy grid-connected impact and enhancing power grid stability. Underground reservoirs, such as lining rock mass caverns or salt caverns, are a central component of the CAES system. In the primary design stage of CAES power station, it is important to quickly and accurately estimate the required volume (storage capacity) of the gas storage and the gas filling/discharging rate (gas filling/discharging rate) in the gas filling/discharging process, which directly relate to the energy storage capacity, power output, economy and safety of the system. In the prior art, the estimated reservoir capacity and the inflation and deflation rate are mostly dependent on a numerical simulation method. The numerical simulation method is complex in calculation, time-consuming, high in requirement on professional background of a user and inconvenient for rapid engineering design and scheme comparison. In addition, the prior art lacks a generalized design tool that can intuitively and systematically directly relate design objectives (e.g., nominal Yong storage capacity, maximum allowable operating pressure) to two key design parameters, namely reservoir capacity, charge-discharge rate. Therefore, a method for rapidly and accurately determining the storage capacity and the charge and discharge rate of the CAES gas storage is urgently needed, which not only considers the actual thermodynamic process (non-adiabatic conditions), but also is convenient for engineering application. Disclosure of Invention In order to overcome the defects of the prior art, the invention discloses a method and a system for determining the storage capacity and the inflation and deflation rate of a compressed air energy storage gas storage (especially a lining rock mass cave (LRC) or a salt cave) based on thermodynamic response differential decomposition, and provides an efficient and accurate theoretical tool for CAES gas storage design. In order to achieve the above object, the present invention provides the following solutions: A compressed air energy storage gas storage reservoir capacity and charging and discharging rate determining method based on thermodynamic response difference decomposition comprises the following steps: Establishing a differential model of the thermodynamic response of the gas storage, and obtaining the maximum Yong which can be stored in the gas storage and the maximum pressure reached by the air in the gas storage based on the differential model of the thermodynamic response of the gas storage; and respectively drawing the contour lines of the maximum Yong and the maximum pressure on a two-dimensional plane of the reservoir capacity-the inflation and deflation rate, and determining the reservoir capacity and inflation and deflation rate feasible design values which simultaneously meet Yong storage and pressure constraint by utilizing the intersection points of the two contour lines to finish the optimal design of the compressed air energy storage and gas storage. Preferably, the method for establishing the differential thermodynamic response model of the gas storage comprises the following steps: Based on a mass conservation equation, an energy conservation equation and a gas state equation, a control equation set for describing air temperature, pressure, quality and surrounding rock temperature change of the gas storage in the process of charging and discharging circulation is established; Discretizing the time and space, solving the control equation set by adopting a differential method to obtain dynamic response of air pressure, temperature, Yong and surrounding rock temperature field in the air reservoir changing along with time under the input condition of preset reservoir capacity and air charging and discharging speed, and completing construction of a thermodynamic response differential model of the air reservoir. Preferably, the method for constructing the mass conservation equation, the energy conservation equation and the gas state equation comprises the following steps: constructing a mass conservation equation based on the air release mass flow and the air filling mass flow in the air storage; constructing a hole wall heat flow equation based on the hole wall area, the average heat exchange coefficient of the hole wall and air, the air temperature in the air storage and