Compressed carbon dioxide energy storage system real-time control method, device, equipment and medium

Abstract

The invention provides a real-time control method, device and equipment for a compressed carbon dioxide energy storage system and a medium, relates to the technical field of compressed energy storage, and is applied to the compressed carbon dioxide energy storage system which comprises a high-pressure gas storage unit with a carbon dioxide pipeline at the bottom end and a liquid pump. The method comprises the following steps: acquiring state data of a high-pressure gas storage unit at an initial moment, and determining thermodynamic parameters at the initial moment according to the state data at the initial moment; a temperature value and a pressure value at the current moment are obtained according to the current moment; determining a thermodynamic parameter at the current moment according to the thermodynamic parameter at the initial moment, the state data at the initial moment and the temperature value at the current moment; according to the thermodynamic parameter at the current moment and the pressure value at the current moment, generating a thermodynamic change parameter at the next moment, and according to the thermodynamic change parameter, performing frequency conversion control on operation of the liquid pump; and the steps are circulated until energy release of the compressed carbon dioxide energy storage system is completed. The energy utilization efficiency can be improved.

Description

Technical Field

[0001] The present invention relates to the field of compressed energy storage technology, and in particular to a real-time control method, device, equipment and medium for a compressed carbon dioxide energy storage system. Background Art

[0002] Compressed CO2 energy storage uses electricity to compress and store CO2 in geological structures or man-made tanks. When needed, the high-pressure CO2 is released to drive turbines for power generation. This technology is primarily used for large-scale grid energy storage to balance grid loads, increase renewable energy utilization, address the mismatch between supply and demand in the renewable energy power generation industry, and assist in peak-shaving.

[0003] In related technologies, compressed carbon dioxide is released through an expander, converting the stored high-pressure gas energy into mechanical energy, which is then used to generate electricity through a generator. During the release process, supercritical carbon dioxide in compressed carbon dioxide energy storage systems liquefies, necessitating a heating device. To ensure the operating efficiency of the expander, the current main methods are to operate the expander in a sliding pressure mode to ensure isentropic efficiency, or to maintain a stable inlet pressure using a throttle valve. However, the former is difficult to control, making it difficult to maintain a constant output power, while the latter results in significant exergy losses, reducing the system's electrical-to-electrical conversion efficiency. Summary of the Invention

[0004] The present invention aims to solve at least one of the above problems.

[0005] To solve the above problems, the present invention provides a method, device, equipment and medium for real-time control of a compressed carbon dioxide energy storage system.

[0006] In a first aspect, the present invention provides a real-time control method for a compressed carbon dioxide energy storage system, which is applied to a compressed carbon dioxide energy storage system. The compressed carbon dioxide energy storage system includes a high-pressure gas storage unit with a carbon dioxide pipeline at its bottom end and a liquid pump arranged at the outlet of the carbon dioxide pipeline. The liquid pump is used to control the energy release pressure of the compressed carbon dioxide energy storage system. A temperature sensor and a pressure sensor are provided inside the high-pressure gas storage unit. The temperature sensor is used to obtain the temperature value of the high-pressure gas storage unit in real time. The pressure sensor is used to obtain the pressure value of the high-pressure gas storage unit in real time. The real-time control method of the compressed carbon dioxide energy storage system includes: S1, obtaining state data of the high-pressure gas storage unit at an initial moment, and determining thermodynamic parameters at the initial moment based on the state data at the initial moment; S2, obtaining the current temperature value and the current pressure value of the high-pressure gas storage unit 1 through the temperature sensor and the pressure sensor respectively; S3, determining the thermodynamic parameters at the current moment according to the thermodynamic parameters at the initial moment, the state data at the initial moment, and the temperature value at the current moment; S4, generating a thermodynamic change parameter at a next moment based on the thermodynamic parameter at the current moment and the pressure value at the current moment, and frequency-controlling the operation of the liquid pump based on the thermodynamic change parameter at the next moment; S5, taking the state data at the current moment as the state data at the initial moment, and looping through steps S1 to S5 until the compressed carbon dioxide energy storage system completes energy release.

[0007] Optionally, the state data at the initial moment includes the volume of the high-pressure gas storage unit, the temperature value at the initial moment, the pressure value at the initial moment, the gas mass flow rate during the energy release process, the gas density at the initial moment, and the total gas mass at the initial moment, wherein the volume and the gas mass flow rate are fixed; The obtaining of the initial state data of the high-pressure gas storage unit includes: Obtaining the preset volume, the temperature value at the initial moment, the pressure value at the initial moment, and the gas mass flow rate; Determining the gas density at the initial moment using thermodynamic software based on the temperature value and the pressure value at the initial moment; The total mass of the gas at the initial moment is determined according to the volume and the gas density at the initial moment.

[0008] Optionally, the thermodynamic parameters at the initial moment include a specific thermodynamic energy parameter at the initial moment, a specific enthalpy parameter at the initial moment, and a specific entropy parameter at the initial moment; Determining the thermodynamic parameters at the initial moment according to the state data at the initial moment includes: According to the temperature value at the initial moment and the pressure value at the initial moment, the thermodynamic software is used to determine the specific thermodynamic energy parameter at the initial moment, the specific enthalpy parameter at the initial moment, and the specific entropy parameter at the initial moment.

[0009] Optionally, the step S3 of determining the thermodynamic parameters at the current moment according to the thermodynamic parameters at the initial moment, the state data at the initial moment, and the temperature value at the current moment includes: Obtaining the gas mass flow rate of the high-pressure gas storage unit during the energy release process, and determining the total mass of gas in the high-pressure gas storage unit at a current moment based on the gas mass flow rate; Determining specific thermodynamic energy parameters at a current moment based on the gas mass flow rate, the total mass of the gas, the state data at the initial moment, and the law of conservation of energy of unsteady flow in an open system; According to the temperature value at the current moment and the pressure value at the current moment, a specific enthalpy parameter at the current moment and a specific entropy parameter at the current moment are determined respectively.

[0010] Optionally, determining the specific thermodynamic energy parameter at the current moment based on the gas mass flow rate, the total mass of the gas, the state data at the initial moment, and the law of conservation of energy of unsteady flow of an open system includes: The specific thermodynamic energy parameter at the current moment is determined using a specific thermodynamic energy parameter determination formula based on the gas mass flow rate, the total mass of the gas, the state data at the initial moment, and the law of conservation of energy of the unsteady flow of the opening system. The specific thermodynamic energy parameter determination formula includes: ; in, For the current moment, is the initial moment, is the time interval, is the specific thermodynamic energy parameter at the current moment, m is the total mass of the gas at the initial moment, is the specific thermodynamic energy parameter at the initial moment, mf is the gas mass flow rate, h(t) is the specific enthalpy parameter at the initial moment, (t) is the specific enthalpy parameter of carbon dioxide in saturated liquid state at the pressure at time t, is the total mass of gas in the high-pressure gas storage unit 1 at the current moment.

[0011] Optionally, the thermodynamic change parameters at the next moment include a dryness change parameter at the next moment, a pressure change parameter inside the high-pressure gas storage unit, and a pressure head change parameter of the liquid pump. Generating the thermodynamic change parameters at the next moment based on the thermodynamic parameters at the current moment and the pressure value at the current moment includes: generating the dryness change parameter according to the thermodynamic parameter at the current moment; generating a pressure change parameter inside the high-pressure gas storage unit according to the current pressure value; The pressure head variation parameter of the liquid pump is generated according to the internal pressure variation parameter of the high-pressure gas storage unit and the preset outlet pressure value.

[0012] Optionally, the frequency conversion control of the operation of the liquid pump according to the thermodynamic change parameter includes: determining the state of high-pressure carbon dioxide at the outlet of the high-pressure gas storage unit according to the dryness change parameter; The operation of the liquid pump is controlled by frequency conversion according to the high-pressure carbon dioxide state and the pressure head change parameter of the liquid pump.

[0013] In a second aspect, the present invention provides a real-time control device for a compressed carbon dioxide energy storage system, which is applied to a compressed carbon dioxide energy storage system. The compressed carbon dioxide energy storage system includes a high-pressure gas storage unit with a carbon dioxide pipeline at the bottom and a liquid pump arranged at the outlet of the carbon dioxide pipeline. The liquid pump is used to control the energy release pressure of the compressed carbon dioxide energy storage system. A temperature sensor and a pressure sensor are provided inside the high-pressure gas storage unit. The temperature sensor is used to obtain the temperature value of the high-pressure gas storage unit in real time, and the pressure sensor is used to obtain the pressure value of the high-pressure gas storage unit in real time. The real-time control device for the compressed carbon dioxide energy storage system comprises: The initial module is used to obtain the initial state data of the high-pressure gas storage unit and determine the thermodynamic parameters at the initial time based on the initial state data. an acquisition module, configured to acquire a current temperature value and a current pressure value of the high-pressure gas storage unit through the temperature sensor and the pressure sensor, respectively; a parameter module, configured to determine the thermodynamic parameters at the current moment based on the thermodynamic parameters at the initial moment, the state data at the initial moment, and the temperature value at the current moment; a control module, configured to generate a thermodynamic change parameter at a next moment based on the thermodynamic parameter at the current moment and the pressure value at the current moment, and to frequency-control the operation of the liquid pump based on the thermodynamic change parameter at the next moment; A circulation module is used to use the state data at the current moment as the state data at the initial moment, and circulate the steps from the initial module to the circulation module until the compressed carbon dioxide energy storage system completes energy release.

[0014] In a third aspect, the present invention provides an electronic device comprising a memory and a processor; The memory is used to store computer programs; The processor is configured to implement the real-time control method for the compressed carbon dioxide energy storage system as described in the first aspect when executing the computer program.

[0015] In a fourth aspect, the present invention provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the real-time control method for the compressed carbon dioxide energy storage system as described in the first aspect is implemented.

[0016] The beneficial effects of the real-time control method, device, electronic device, and storage medium of the compressed carbon dioxide energy storage system of the present invention are: By arranging the carbon dioxide pipeline and liquid pump at the bottom of the high-pressure gas storage unit, the high-pressure carbon dioxide in the high-pressure gas storage unit can flow out from the bottom of the high-pressure gas storage unit in the form of supercritical state or liquid under the dual action of gravity and pressure difference. No additional heating device is required to make the high-pressure carbon dioxide flow out, which saves operating costs. Then, by determining the thermodynamic parameters at the initial moment based on the state data of the high-pressure gas storage unit at the initial moment, the real-time thermodynamic parameters can be accurately calculated, thereby generating the thermodynamic change parameters at the next moment in the high-pressure gas storage unit, and then the operation of the liquid pump is frequency-controlled according to the thermodynamic change parameters at the next moment, which makes it more convenient to adjust and control the pressure of the high-pressure carbon dioxide at the expander inlet to be constant during the energy release process of the compressed carbon dioxide energy storage system in real time, thereby reducing exergy loss and improving energy utilization efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A flow chart of a real-time control method for a compressed carbon dioxide energy storage system according to an embodiment of the present invention; Figure 2 A schematic structural diagram of a compressed carbon dioxide energy storage system provided in an embodiment of the present invention; Figure 3 A schematic diagram of gas changes in a compressed carbon dioxide energy storage system provided in an embodiment of the present invention; Figure 4 A schematic structural diagram of a real-time control device for a compressed carbon dioxide energy storage system according to an embodiment of the present invention; Figure 5 A schematic structural diagram of an electronic device provided by an embodiment of the present invention.

[0018] Description of reference numerals: 1. High-pressure gas storage unit; 11. Carbon dioxide pipeline; 12. Ball valve; 2. Liquid pump. DETAILED DESCRIPTION

[0019] To make the above-mentioned objects, features, and advantages of the present invention more clearly understood, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings. Although certain embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be construed as being limited to the embodiments described herein. Instead, these embodiments are provided to provide a more thorough and complete understanding of the present invention. It should be understood that the drawings and embodiments of the present invention are for illustrative purposes only and are not intended to limit the scope of protection of the present invention.

[0020] It should be understood that the various steps described in the method embodiments of the present invention may be performed in different orders and / or in parallel. In addition, the method embodiments may include additional steps and / or omit the steps shown. The scope of the present invention is not limited in this respect.

[0021] The term "including" and its variations used in this document are open inclusions, that is, "including but not limited to"; the term "based on" means "based at least in part on"; the term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one other embodiment"; the term "some embodiments" means "at least some embodiments"; the term "optionally" means "optional embodiments". The relevant definitions of other terms will be given in the following description. It should be noted that the concepts of "first", "second", etc. mentioned in the present invention are only used to distinguish different devices, modules or units, and are not used to limit the order or interdependence of the functions performed by these devices, modules or units.

[0022] It should be noted that the modifications of "one" and "multiple" mentioned in the present invention are illustrative rather than restrictive. Those skilled in the art should understand that unless otherwise clearly indicated in the context, it should be understood as "one or more".

[0023] The names of the messages or information exchanged between multiple devices in the embodiments of the present invention are only used for illustrative purposes and are not used to limit the scope of these messages or information.

[0024] In response to the problems existing in the above-mentioned related technologies, this embodiment provides a real-time control method, device, equipment and medium for a compressed carbon dioxide energy storage system.

[0025] The embodiment of the present invention provides a real-time control method for a compressed carbon dioxide energy storage system, which is applied to a compressed carbon dioxide energy storage system, such as Figure 2 As shown, the compressed carbon dioxide energy storage system includes a high-pressure gas storage unit 1 with a carbon dioxide pipeline 11 at the bottom end and a liquid pump 2 arranged at the outlet of the carbon dioxide pipeline 11. The liquid pump 2 is used to control the energy release pressure of the compressed carbon dioxide energy storage system. A temperature sensor and a pressure sensor are provided inside the high-pressure gas storage unit 1. The temperature sensor is used to obtain the temperature value of the high-pressure gas storage unit 1 in real time, and the pressure sensor is used to obtain the pressure value of the high-pressure gas storage unit 1 in real time.

[0026] Specifically, a carbon dioxide pipeline 11 is provided at the bottom of the high-pressure gas storage unit 1 of the compressed carbon dioxide energy storage system. That is, the carbon dioxide outlet in the high-pressure gas storage unit 1 is located at the bottom, allowing the high-pressure carbon dioxide in the high-pressure gas storage unit 1 to flow out of the bottom of the high-pressure gas storage unit in a supercritical or liquid state under the dual effects of gravity and pressure differential. The carbon dioxide pipeline 11 is also sequentially provided with a ball valve 12 and a liquid pump 2 along the direction of high-pressure carbon dioxide release. The ball valve 12 is used to control the gas mass flow rate during the energy release process. By adjusting the opening of the ball valve, the mass flow rate of the carbon dioxide outflow can be precisely controlled to ensure a constant energy release flow rate. The liquid pump 2 can be a corrosion-resistant centrifugal pump and is used to control the energy release pressure of the compressed carbon dioxide energy storage system to be constant. A temperature sensor and a pressure sensor are provided within the high-pressure gas storage unit 1. The temperature sensor is used to obtain the temperature value of the high-pressure gas storage unit 1 in real time, and the pressure sensor is used to obtain the pressure value of the high-pressure gas storage unit 1 in real time to achieve real-time monitoring and provide a basis for subsequent parameter calculations.

[0027] like Figure 1 As shown, the real-time control method of the compressed carbon dioxide energy storage system includes: S1, obtaining state data of the high-pressure gas storage unit 1 at an initial moment, and determining thermodynamic parameters at the initial moment according to the state data at the initial moment.

[0028] Specifically, the state data at the initial moment include the volume of the high-pressure gas storage unit 1, the temperature value at the initial moment, the pressure value at the initial moment, the gas mass flow rate during the energy release process, the gas density at the initial moment, and the total gas mass at the initial moment. Among them, the volume, gas mass flow rate, the temperature value at the initial moment, and the pressure value at the initial moment are preset values and can be set according to actual conditions. For example, the volume is set to 80 m 3 The gas mass flow rate is set to 5 kg / s, the initial temperature is set to 308.15 K, and the initial pressure is set to 10 MPa. The volume and gas mass flow rate remain constant, and neither changes with increasing energy release time. Based on the initial state data, thermodynamic parameters at the initial time can be determined using thermodynamic software such as refprop. The initial thermodynamic parameters include the specific thermodynamic energy parameter, the specific enthalpy parameter, and the specific entropy parameter. The specific entropy parameter can be used to verify the accuracy of the calculation process.

[0029] S2, respectively obtaining the current temperature value and the current pressure value of the high-pressure gas storage unit 1 through the temperature sensor and the pressure sensor.

[0030] Specifically, the temperature value and pressure value of the high-pressure gas storage unit 1 at the current moment are obtained through the temperature sensor and the pressure sensor respectively, that is, the temperature value and pressure value of the high-pressure gas storage unit 1 are obtained in real time, so as to realize real-time monitoring and provide a basis for subsequent parameter calculation.

[0031] S3, determining the thermodynamic parameters at the current moment according to the thermodynamic parameters at the initial moment, the state data at the initial moment, and the temperature value at the current moment.

[0032] Specifically, based on the thermodynamic parameters at the initial moment, the state data at the initial moment, the temperature value at the current moment, and the pressure value at the current moment, thermodynamic software, such as refprop software, can be used to determine the thermodynamic parameters at the current moment and the state data at the current moment, thereby facilitating the subsequent calculation of the thermodynamic change parameters at the next moment.

[0033] S4, generating thermodynamic change parameters at the next moment according to the thermodynamic parameters at the current moment and the pressure value at the current moment, and frequency-controlling the operation of the liquid pump 2 according to the thermodynamic change parameters at the next moment.

[0034] Specifically, based on the thermodynamic parameters at the current moment and the state data at the current moment, the thermodynamic change parameters at the next moment are generated, so that at the next moment, based on the thermodynamic change parameters at the next moment, the operation of the liquid pump 2 is frequency-controlled. The thermodynamic change parameters at the next moment include the dryness change parameters at the next moment, the internal pressure change parameters of the high-pressure gas storage unit 1, and the pressure head change parameters of the liquid pump. Dryness refers to the proportion of saturated gaseous carbon dioxide in the gas-liquid coexisting carbon dioxide in the high-pressure gas storage unit 1. The dryness change parameters can clarify the internal state of the high-pressure gas storage unit 1, such as temperature and pressure, thereby determining the state of the compressed carbon dioxide, that is, Figure 3 As shown, as the energy release time increases, when the dryness value is in the interval [0, 1], the high-pressure carbon dioxide in the high-pressure gas storage unit 1 is converted from a supercritical state to a gas-liquid coexistence state, and the gas-liquid boundary moves from the top to the bottom of the high-pressure gas storage unit 1. During this period, the high-pressure carbon dioxide can be released. As the energy release time increases, when it is outside the interval [0, 1], for example, when it is greater than 1, as shown in FIG. Figure 3As shown, the high-pressure carbon dioxide in the high-pressure gas storage unit 1 is converted from a gas-liquid coexistence state to a gaseous state. At this time, the compressed carbon dioxide release operation is stopped and the energy release process is completed. The internal pressure change parameter of the high-pressure gas storage unit 1 refers to how the internal pressure of the high-pressure gas storage unit 1 should change with the energy release time. The liquid pump pressure head change parameter refers to how the pressure head of the liquid pump should change with the energy release time. The pressure head of the liquid pump is the difference between the outlet pressure and the inlet pressure of the liquid pump. Among them, the outlet pressure is a fixed value and can be set according to actual conditions. For example, the preset outlet pressure value is set to 10Mpa, and the inlet pressure is the same as the internal pressure of the high-pressure gas storage unit 1. Therefore, the liquid pump pressure head change parameter can be determined by the outlet pressure and the internal pressure change parameter. Then, based on the similarity law and the liquid pump pressure head change parameter, the operating frequency of the liquid pump 2 is determined. The operation of the liquid pump 2 can be controlled by frequency conversion, thereby ensuring that the energy release pressure of the high-pressure carbon dioxide in the compressed carbon dioxide energy storage system is constant, that is, the expander inlet pressure is kept constant.

[0035] S5, taking the state data at the current moment as the state data at the initial moment, and looping through steps S1 to S5 until the compressed carbon dioxide energy storage system completes energy release.

[0036] Specifically, after the next moment of control is completed, steps S1 to S5 are repeated using the current state data as the initial state data, i.e., the next round of control is performed to control the entire energy release process. Steps S1 to S5 are then repeated in sequence until the compressed carbon dioxide energy storage system completes energy release, achieving real-time control of the entire energy release process. The energy release process can be determined based on a dryness variation parameter; when the dryness value is outside the [0, 1] interval, energy release is complete.

[0037] In this embodiment, the carbon dioxide pipeline 11 and liquid pump 2 disposed at the bottom of the high-pressure gas storage unit 1 allow the high-pressure carbon dioxide within the high-pressure gas storage unit 1 to flow out of the bottom of the high-pressure gas storage unit 1 in a supercritical or liquid state under the dual effects of gravity and pressure differential. No additional heating device is required to cause the high-pressure carbon dioxide to flow out of the top as a gas, thus saving operating costs. Furthermore, by determining the thermodynamic parameters at the initial moment based on the initial state data of the high-pressure gas storage unit 1, the real-time thermodynamic parameters can be accurately calculated, thereby generating the thermodynamic change parameters within the high-pressure gas storage unit 1 at the next moment. Based on the thermodynamic change parameters at the next moment, the operation of the liquid pump 2 is frequency-controlled to maintain a constant energy release pressure of the compressed carbon dioxide energy storage system, that is, to maintain a constant expander inlet pressure, thereby reducing exergy losses and improving electrical-to-electrical conversion efficiency. Furthermore, by frequency-controlling the operation of the liquid pump, the problem of supercritical carbon dioxide liquefaction within the high-pressure gas storage unit 1 during energy release can be utilized, thereby enhancing energy utilization efficiency, increasing the minimum operating pressure of the high-pressure gas storage unit 1, and improving the utilization efficiency of the high-pressure gas storage unit's container.

[0038] Optionally, the state data at the initial moment includes the volume of the high-pressure gas storage unit 1, the temperature value at the initial moment, the pressure value at the initial moment, the gas mass flow rate during the energy release process, the gas density at the initial moment, and the total gas mass at the initial moment, wherein the volume and the gas mass flow rate are fixed; The obtaining of the initial state data of the high-pressure gas storage unit 1 includes: Obtaining the preset volume, the temperature value at the initial moment, the pressure value at the initial moment, and the gas mass flow rate; Determining the gas density at the initial moment using thermodynamic software based on the temperature value and the pressure value at the initial moment; The total mass of the gas at the initial moment is determined according to the volume and the gas density at the initial moment.

[0039] Specifically, the volume, the temperature value at the initial moment, the pressure value at the initial moment, and the gas mass flow rate are all preset values. Based on the temperature value at the initial moment and the pressure value at the initial moment, thermodynamic software, such as refprop software, can be used to determine the gas density at the initial moment. Based on the volume and the gas density at the initial moment, the total mass of the gas at the initial moment can be determined using a mass formula. The mass formula includes: ; Where m is the total mass of gas at the initial moment, V is the volume, is the gas density at the initial moment.

[0040] Optionally, the thermodynamic parameters at the initial moment include a specific thermodynamic energy parameter at the initial moment, a specific enthalpy parameter at the initial moment, and a specific entropy parameter at the initial moment; Determining the thermodynamic parameters at the initial moment according to the state data at the initial moment includes: According to the temperature value at the initial moment and the pressure value at the initial moment, the thermodynamic software is used to determine the specific thermodynamic energy parameter at the initial moment, the specific enthalpy parameter at the initial moment, and the specific entropy parameter at the initial moment.

[0041] Specifically, based on the temperature value and the pressure value at the initial moment, thermodynamic software, such as refprop software, can be used to determine the specific thermodynamic energy parameter at the initial moment, the specific enthalpy parameter at the initial moment, and the specific entropy parameter at the initial moment.

[0042] Optionally, the step S3 of determining the thermodynamic parameters at the current moment according to the thermodynamic parameters at the initial moment, the state data at the initial moment, and the temperature value at the current moment includes: Obtaining the gas mass flow rate of the high-pressure gas storage unit 1 during the energy release process, and determining the total mass of the gas in the high-pressure gas storage unit 1 at the current moment based on the gas mass flow rate; Determining specific thermodynamic energy parameters at a current moment based on the gas mass flow rate, the total mass of the gas, the state data at the initial moment, and the law of conservation of energy of unsteady flow in an open system; According to the temperature value at the current moment and the pressure value at the current moment, a specific enthalpy parameter at the current moment and a specific entropy parameter at the current moment are determined respectively.

[0043] Specifically, the gas mass flow rate of the high-pressure gas storage unit 1 during the energy release process is obtained. The gas mass flow rate refers to the mass of supercritical or liquid high-pressure carbon dioxide flowing out of the high-pressure gas storage unit 1 per unit time. The total mass of gas in the high-pressure gas storage unit 1 at the current moment is the total mass of high-pressure carbon dioxide remaining in the high-pressure gas storage unit 1 after a time interval. According to the gas mass flow rate and the mass conservation formula, the total mass of gas in the high-pressure gas storage unit 1 at the current moment is determined. The mass conservation formula includes: ; in, is the total mass of gas in the high-pressure gas storage unit 1 at the current moment, is the total mass of gas in the high-pressure gas storage unit 1 at the initial moment, is the gas mass flow rate, is the time interval.

[0044] Then, based on the total mass of gas in the high-pressure gas storage unit 1 and the volume at the current moment, the density at the current moment is determined using a density formula, which includes: ; Where m is the total mass of gas in the high-pressure gas storage unit 1 at the current moment, V is the volume, is the gas density at the current moment.

[0045] Then, according to the law of conservation of energy and mass of unsteady flow in an open system, the specific thermodynamic energy parameters at the current moment are determined. Then, according to the specific thermodynamic energy parameters at the current moment and the density at the current moment, the refprop software and the thermodynamic parameter formula group are used to determine the specific enthalpy parameters and the specific entropy parameters at the current moment on the physical property curve. The thermodynamic parameter formula group includes: ; in ，h is the specific enthalpy parameter at the current moment ，s is the specific entropy parameter at the current moment ， are all functions in the refprop software, u is the specific thermodynamic energy parameter at the current moment, is the density at the current moment.

[0046] Optionally, determining the specific thermodynamic energy parameter at the current moment based on the gas mass flow rate, the total mass of the gas, the state data at the initial moment, and the law of conservation of energy of unsteady flow of an open system includes: The specific thermodynamic energy parameter at the current moment is determined using a specific thermodynamic energy parameter determination formula based on the gas mass flow rate, the total mass of the gas, the state data at the initial moment, and the law of conservation of energy of the unsteady flow of the opening system. The specific thermodynamic energy parameter determination formula includes: ; in, For the current moment, is the initial moment, is the time interval, is the specific thermodynamic energy parameter at the current moment, m is the total mass of the gas at the initial moment, is the specific thermodynamic energy parameter at the initial moment, mf is the gas mass flow rate, h(t) is the specific enthalpy parameter at the initial moment, (t) is the specific enthalpy parameter of carbon dioxide in saturated liquid state at the pressure at time t, is the total mass of gas in the high-pressure gas storage unit 1 at the current moment.

[0047] Specifically, is the specific enthalpy parameter of carbon dioxide in a saturated liquid state at the pressure at time t. Because when high-pressure carbon dioxide is in a gas-liquid coexistence state, the liquid carbon dioxide released at the bottom of the high-pressure gas storage unit 1 is in a saturated state. In the subsequent cycle calculation process, the specific thermodynamic energy parameter determination formula is still used to determine the specific thermodynamic energy parameter at the next moment. The parameter at the initial moment is replaced by the parameter at the current moment of the previous round to obtain the specific thermodynamic energy parameter at the next moment. That is, in the subsequent cycle calculation process, For the next moment, For the current moment, is the specific thermodynamic energy parameter at the next moment, m is the total mass of the gas at the current moment, is the specific thermodynamic energy parameter at the current moment, mf is the gas mass flow rate, h(t) is the specific enthalpy parameter at the current moment, (t) is the specific enthalpy parameter of carbon dioxide in saturated liquid state at the pressure at time t, is the total mass of gas in the high-pressure gas storage unit 1 at the next moment. The other formulas are similar and will not be repeated here.

[0048] Optionally, the thermodynamic change parameters at the next moment include a dryness change parameter at the next moment, a pressure change parameter inside the high-pressure gas storage unit 1, and a pressure head change parameter of the liquid pump. Generating the thermodynamic change parameters at the next moment based on the thermodynamic parameters at the current moment and the pressure value at the current moment includes: generating the dryness change parameter according to the thermodynamic parameter at the current moment; generating a pressure change parameter inside the high-pressure gas storage unit 1 according to the current pressure value; The pressure head variation parameter of the liquid pump is generated according to the internal pressure variation parameter of the high-pressure gas storage unit 1 and the preset outlet pressure value.

[0049] Specifically, the dryness change parameter is generated using a dryness formula according to the thermodynamic parameters at the current moment. The dryness formula includes: ; Where x is the dryness, is the enthalpy of gas-liquid coexistence of carbon dioxide, is the enthalpy of saturated liquid carbon dioxide, is the enthalpy of saturated gaseous carbon dioxide. In addition, the dryness can also be determined by using the refprop software, using density and specific thermodynamic energy to determine the dryness at that moment from the physical property curve.

[0050] According to the pressure value at the current moment, the internal pressure change parameter of the high-pressure gas storage unit 1 is generated. The liquid pump pressure head change parameter refers to the curve of the pressure head of the liquid pump changing with the energy release time. The pressure head of the liquid pump is the difference between the outlet pressure and the inlet pressure of the liquid pump. Among them, the outlet pressure is a fixed value and can be set according to actual conditions. For example, the preset outlet pressure value is set to 10Mpa, and the inlet pressure is the same as the internal pressure of the high-pressure gas storage unit 1. Therefore, the liquid pump pressure head change parameter can be determined by the outlet pressure and the internal pressure change parameter.

[0051] Optionally, the variable frequency control of the operation of the liquid pump 2 according to the thermodynamic change parameter includes: determining the state of high-pressure carbon dioxide at the outlet of the high-pressure gas storage unit 1 according to the dryness change parameter; The operation of the liquid pump 2 is controlled by frequency conversion according to the high-pressure carbon dioxide state and the pressure head change parameter of the liquid pump.

[0052] Specifically, the state of high-pressure carbon dioxide at the outlet of the high-pressure gas storage unit 1 is determined according to the dryness change parameter, such as Figure 3 As shown, when the high-pressure carbon dioxide at the outlet of high-pressure gas storage unit 1 is in a supercritical state or a gas-liquid coexistence state, energy release can be performed. The liquid pump pressure head variation parameters are determined based on the change in the high-pressure carbon dioxide state within high-pressure gas storage unit 1 over the energy release time. The liquid pump frequency is dynamically adjusted according to the similarity law, and the operation of liquid pump 2 is controlled by frequency conversion, thereby achieving precise control of the energy release pressure, i.e., the expander inlet pressure. The specific steps include determining initial conditions, calculating target state parameters, deriving a new frequency using the similarity law, and finally setting this frequency in the frequency converter. Dynamically adjusting the liquid pump frequency compensates for pressure losses within the high-pressure gas storage unit, ensuring a constant expander inlet pressure and, consequently, the system's stable output power. When the high-pressure carbon dioxide at the outlet of high-pressure gas storage unit 1 is in a gaseous state, the energy release operation ceases.

[0053] like Figure 4 As shown, an embodiment of the present invention provides a real-time control device for a compressed carbon dioxide energy storage system, which is applied to a compressed carbon dioxide energy storage system. The compressed carbon dioxide energy storage system includes a high-pressure gas storage unit 1 with a carbon dioxide pipeline 11 at the bottom end and a liquid pump 2 arranged at the outlet of the carbon dioxide pipeline 11. The liquid pump 2 is used to control the energy release pressure of the compressed carbon dioxide energy storage system. A temperature sensor and a pressure sensor are provided inside the high-pressure gas storage unit 1. The temperature sensor is used to obtain a real-time temperature value of the high-pressure gas storage unit 1, and the pressure sensor is used to obtain a real-time pressure value of the high-pressure gas storage unit 1. The real-time control device for the compressed carbon dioxide energy storage system comprises: The initial module is used to obtain the initial state data of the high-pressure gas storage unit 1 and determine the thermodynamic parameters at the initial time based on the initial state data. an acquisition module, configured to acquire the current temperature value and the current pressure value of the high-pressure gas storage unit 1 through the temperature sensor and the pressure sensor, respectively; a parameter module, configured to determine the thermodynamic parameters at the current moment based on the thermodynamic parameters at the initial moment, the state data at the initial moment, and the temperature value at the current moment; a control module, configured to generate a thermodynamic change parameter at a next moment according to the thermodynamic parameter at the current moment and the pressure value at the current moment, and to frequency-control the operation of the liquid pump 2 according to the thermodynamic change parameter at the next moment; A circulation module is used to use the state data at the current moment as the state data at the initial moment, and circulate the steps from the initial module to the circulation module until the compressed carbon dioxide energy storage system completes energy release.

[0054] like Figure 5 As shown, an electronic device 500 provided by an embodiment of the present invention includes a memory 510 and a processor 520; the memory 510 is used to store a computer program; the processor 520 is used to implement the above-mentioned real-time control method of the compressed carbon dioxide energy storage system when executing the computer program.

[0055] In other words, an electronic device 500 includes a memory 510 and a processor 520 coupled to the memory 510; the memory 510 is configured to store a computer program; and the processor 520 is configured to perform the following operations when executing the computer program: S1, obtaining state data of the high-pressure gas storage unit 1 at an initial moment, and determining thermodynamic parameters at the initial moment based on the state data at the initial moment; S2, obtaining the current temperature value and the current pressure value of the high-pressure gas storage unit 1 through the temperature sensor and the pressure sensor respectively; S3, determining the thermodynamic parameters at the current moment according to the thermodynamic parameters at the initial moment, the state data at the initial moment, and the temperature value at the current moment; S4, generating a thermodynamic change parameter at a next moment based on the thermodynamic parameter at the current moment and the pressure value at the current moment, and frequency-controlling the operation of the liquid pump 2 based on the thermodynamic change parameter at the next moment; S5, taking the state data at the current moment as the state data at the initial moment, and looping through steps S1 to S5 until the compressed carbon dioxide energy storage system completes energy release.

[0056] An embodiment of the present invention provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the above-mentioned method for real-time control of a compressed carbon dioxide energy storage system is implemented.

[0057] In other words, a non-volatile computer-readable storage medium stores a computer program, which, when executed by a processor, causes the processor to perform the following operations: S1, obtaining state data of the high-pressure gas storage unit 1 at an initial moment, and determining thermodynamic parameters at the initial moment based on the state data at the initial moment; S2, obtaining the current temperature value and the current pressure value of the high-pressure gas storage unit 1 through the temperature sensor and the pressure sensor respectively; S3, determining the thermodynamic parameters at the current moment according to the thermodynamic parameters at the initial moment, the state data at the initial moment, and the temperature value at the current moment; S4, generating a thermodynamic change parameter at a next moment based on the thermodynamic parameter at the current moment and the pressure value at the current moment, and frequency-controlling the operation of the liquid pump 2 based on the thermodynamic change parameter at the next moment; S5, taking the state data at the current moment as the state data at the initial moment, and looping through steps S1 to S5 until the compressed carbon dioxide energy storage system completes energy release.

[0058] An electronic device 500 that can serve as a server or client of the present invention will now be described, which is an example of a hardware device that can be applied to various aspects of the present invention. The electronic device 500 is intended to represent various forms of digital electronic computer devices, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device 500 can also represent various forms of mobile devices, such as personal digital assistants, cellular phones, smart phones, wearable devices, and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the present invention described and / or required herein.

[0059] Electronic device 500 includes a computing unit that can perform various appropriate actions and processes based on a computer program stored in a read-only memory (ROM) or loaded from a storage unit into a random access memory (RAM). The RAM can also store various programs and data required for device operation. The computing unit, ROM, and RAM are interconnected via a bus. An input / output (I / O) interface is also connected to the bus.

[0060] Those skilled in the art will appreciate that all or part of the processes in the above-described method embodiments can be implemented through computer program instructions and associated hardware. The program can be stored in a computer-readable storage medium, and when executed, the program can include the processes in the above-described method embodiments. The storage medium can be a magnetic disk, an optical disk, a read-only memory (ROM), or a random access memory (RAM). In this application, the units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, i.e., they may be located in a single location or distributed across multiple network elements. Some or all of these units can be selected based on actual needs to achieve the objectives of the embodiments of the present invention. Furthermore, the functional units in the various embodiments of the present invention can be integrated into a single processing unit, each unit can exist physically separately, or two or more units can be integrated into a single unit. These integrated units can be implemented in either hardware or software functional units.

[0061] Although the present invention is disclosed as above, the protection scope of the present invention is not limited thereto. Those skilled in the art may make various changes and modifications without departing from the spirit and scope of the present invention, and these changes and modifications will fall within the protection scope of the present invention.

Claims

1. A real-time control method for a compressed carbon dioxide energy storage system, characterized in that: The invention is applied to a compressed carbon dioxide energy storage system, wherein the compressed carbon dioxide energy storage system comprises a high-pressure gas storage unit (1) having a carbon dioxide pipeline (11) at the bottom end thereof and a liquid pump (2) arranged at the outlet of the carbon dioxide pipeline (11), wherein the liquid pump (2) is used to control the energy release pressure of the compressed carbon dioxide energy storage system, and a temperature sensor and a pressure sensor are provided inside the high-pressure gas storage unit (1), wherein the temperature sensor is used to obtain the temperature value of the high-pressure gas storage unit (1) in real time, and the pressure sensor is used to obtain the pressure value of the high-pressure gas storage unit (1) in real time; The real-time control method of the compressed carbon dioxide energy storage system includes: S1, obtaining state data of the high-pressure gas storage unit (1) at the initial moment, and determining thermodynamic parameters at the initial moment based on the state data at the initial moment; S2, obtaining the current temperature value and the current pressure value of the high-pressure gas storage unit (1) respectively through the temperature sensor and the pressure sensor; S3, determining the thermodynamic parameters at the current moment according to the thermodynamic parameters at the initial moment, the state data at the initial moment, and the temperature value at the current moment; S4, generating a thermodynamic change parameter at the next moment based on the thermodynamic parameter at the current moment and the pressure value at the current moment, and frequency-controlling the operation of the liquid pump (2) based on the thermodynamic change parameter at the next moment; S5, taking the state data at the current moment as the state data at the initial moment, and looping through steps S1 to S5 until the compressed carbon dioxide energy storage system completes energy release.

2. The real-time control method for a compressed carbon dioxide energy storage system according to claim 1, characterized in that: The state data at the initial moment include the volume of the high-pressure gas storage unit (1), the temperature value at the initial moment, the pressure value at the initial moment, the gas mass flow rate during the energy release process, the gas density at the initial moment, and the total gas mass at the initial moment, wherein the volume and the gas mass flow rate are fixed; The obtaining of the initial state data of the high-pressure gas storage unit (1) comprises: Obtaining the preset volume, the temperature value at the initial moment, the pressure value at the initial moment, and the gas mass flow rate; Determining the gas density at the initial moment using thermodynamic software based on the temperature value and the pressure value at the initial moment; The total mass of the gas at the initial moment is determined according to the volume and the gas density at the initial moment.

3. The real-time control method for a compressed carbon dioxide energy storage system according to claim 2, characterized in that: The thermodynamic parameters at the initial moment include a specific thermodynamic energy parameter at the initial moment, a specific enthalpy parameter at the initial moment, and a specific entropy parameter at the initial moment; Determining the thermodynamic parameters at the initial moment according to the state data at the initial moment includes: According to the temperature value at the initial moment and the pressure value at the initial moment, the thermodynamic software is used to determine the specific thermodynamic energy parameter at the initial moment, the specific enthalpy parameter at the initial moment, and the specific entropy parameter at the initial moment.

4. The real-time control method for a compressed carbon dioxide energy storage system according to claim 3, characterized in that: The step S3, determining the thermodynamic parameters at the current moment based on the thermodynamic parameters at the initial moment, the state data at the initial moment, and the temperature value at the current moment, includes: Obtaining the gas mass flow rate of the high-pressure gas storage unit (1) during the energy release process, and determining the total mass of the gas in the high-pressure gas storage unit (1) at the current moment based on the gas mass flow rate, and determining the density at the current moment based on the total mass of the gas in the high-pressure gas storage unit (1) at the current moment and the volume; Determining specific thermodynamic energy parameters at a current moment based on the gas mass flow rate, the total mass of the gas, the state data at the initial moment, and the law of conservation of energy of unsteady flow in an open system; The specific enthalpy parameter at the current moment and the specific entropy parameter at the current moment are determined respectively according to the density at the current moment and the specific thermodynamic energy parameter at the current moment.

5. The real-time control method for a compressed carbon dioxide energy storage system according to claim 4, characterized in that: The determining of the specific thermodynamic energy parameter at the current moment based on the gas mass flow rate, the total mass of the gas, the state data at the initial moment, and the law of conservation of energy of unsteady flow of an open system includes: The specific thermodynamic energy parameter at the current moment is determined using a specific thermodynamic energy parameter determination formula based on the gas mass flow rate, the total mass of the gas, the state data at the initial moment, and the law of conservation of energy of the unsteady flow of the opening system. The specific thermodynamic energy parameter determination formula includes: ； in, For the current moment, is the initial moment, is the time interval, is the specific thermodynamic energy parameter at the current moment, m is the total mass of the gas at the initial moment, is the specific thermodynamic energy parameter at the initial moment, mf is the gas mass flow rate, h(t) is the specific enthalpy parameter at the initial moment, (t) is the specific enthalpy parameter of carbon dioxide in saturated liquid state at the pressure at time t, is the total mass of gas in the high-pressure gas storage unit (1) at the current moment.

6. The real-time control method for a compressed carbon dioxide energy storage system according to claim 1, characterized in that: The thermodynamic change parameters at the next moment include the dryness change parameters at the next moment, the internal pressure change parameters of the high-pressure gas storage unit (1), and the pressure head change parameters of the liquid pump. The thermodynamic change parameters at the next moment are generated based on the thermodynamic parameters at the current moment and the pressure value at the current moment, including: generating the dryness change parameter according to the thermodynamic parameter at the current moment; Generating a pressure change parameter inside the high-pressure gas storage unit (1) according to the pressure value at the current moment; The liquid pump pressure head variation parameter is generated according to the internal pressure variation parameter of the high-pressure gas storage unit (1) and a preset outlet pressure value.

7. The real-time control method for a compressed carbon dioxide energy storage system according to claim 6, characterized in that: The variable frequency control of the operation of the liquid pump (2) according to the thermodynamic change parameter comprises: Determining the state of high-pressure carbon dioxide at the outlet of the high-pressure gas storage unit (1) according to the dryness variation parameter; The operation of the liquid pump (2) is controlled by frequency conversion according to the high-pressure carbon dioxide state and the pressure head change parameter of the liquid pump.

8. A real-time control device for a compressed carbon dioxide energy storage system, characterized in that: The invention is applied to a compressed carbon dioxide energy storage system, wherein the compressed carbon dioxide energy storage system comprises a high-pressure gas storage unit (1) having a carbon dioxide pipeline (11) at the bottom end thereof and a liquid pump (2) arranged at the outlet of the carbon dioxide pipeline (11), wherein the liquid pump (2) is used to control the energy release pressure of the compressed carbon dioxide energy storage system, and a temperature sensor and a pressure sensor are provided inside the high-pressure gas storage unit (1), wherein the temperature sensor is used to obtain the temperature value of the high-pressure gas storage unit (1) in real time, and the pressure sensor is used to obtain the pressure value of the high-pressure gas storage unit (1) in real time; The real-time control device for the compressed carbon dioxide energy storage system comprises: An initial module is used to obtain the state data of the high-pressure gas storage unit (1) at the initial moment, and determine the thermodynamic parameters at the initial moment based on the state data at the initial moment An acquisition module, used for respectively acquiring the current temperature value and the current pressure value of the high-pressure gas storage unit (1) through the temperature sensor and the pressure sensor; a parameter module, configured to determine the thermodynamic parameters at the current moment based on the thermodynamic parameters at the initial moment, the state data at the initial moment, and the temperature value at the current moment; A control module is used to generate a thermodynamic change parameter at a next moment based on the thermodynamic parameter at the current moment and the pressure value at the current moment, and to frequency-control the operation of the liquid pump (2) based on the thermodynamic change parameter at the next moment; A circulation module is used to use the state data at the current moment as the state data at the initial moment, and circulate the steps from the initial module to the circulation module until the compressed carbon dioxide energy storage system completes energy release.

9. An electronic device, characterized in that: including memory and processor; The memory is used to store computer programs; The processor is configured to implement the real-time control method for a compressed carbon dioxide energy storage system according to any one of claims 1 to 7 when executing the computer program.

10. A computer-readable storage medium, characterized in that The storage medium stores a computer program, and when the computer program is executed by the processor, the real-time control method for the compressed carbon dioxide energy storage system according to any one of claims 1 to 7 is implemented.

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