Valve position command generation method and device

Abstract

The application relates to the technical field of compressed air energy storage, and provides a valve position instruction generation method and device. The method comprises the following steps: constructing a valve model, a heat exchanger model and a turbine model; the valve model is used for representing the functional relationship among the air mass flow passing through the valve, the valve position and the pressure difference between the two ends of the valve; the turbine model is used for representing the expansion work capacity and the thermodynamic state change of the air in the turbine. Based on the steady-state operation condition, the valve model, the heat exchanger model and the turbine model are utilized to determine the mapping relationship between the valve position and the discharge power of the adiabatic compressed air energy storage system under different gas storage states, according to different gas storage states and valve positions. Based on the mapping relationship, the valve position instruction is generated according to the current gas storage state and the feedforward power instruction; and the valve position instruction is sent to a valve adjusting device. The valve position instruction generation method provided by the application can improve the accuracy of valve position adjustment and the accuracy of power control of the adiabatic compressed air energy storage system.

Description

Technical Field

[0001] This application relates to the field of compressed air energy storage technology, and in particular to a method and apparatus for generating valve position commands. Background Technology

[0002] As a large-scale, long-term energy storage technology, adiabatic compressed air energy storage (CASS) employs a non-combustion-assisted design, achieving zero carbon emissions throughout the entire process. Currently, CASS has made breakthroughs in key indicators, with some projects achieving an electricity-to-electricity efficiency of 70%, a capacity of 300 megawatts, and a design life of over 20 years. These advancements signify that CASS technology has a solid foundation for large-scale application and are of great significance for achieving dual-carbon strategic goals and building a new power system.

[0003] During the discharge process of an adiabatic compressed air energy storage system, high-pressure air is released from the storage tank, heated by a heat exchanger, and then enters the turbine to expand and perform work, thereby driving the generator to output electrical power. To improve the grid-friendly interaction of adiabatic compressed air energy storage, it is necessary to clarify its power regulation mechanism and the power operating range under different operating conditions. In actual operation, the discharge power is mainly regulated by adjusting the valve opening.

[0004] However, existing discharge power control methods do not adequately consider valve characteristics, resulting in insufficient precision in valve position adjustment and difficulty in accurately matching the target discharge power requirements under different gas storage conditions. This problem limits the power control accuracy of adiabatic compressed air energy storage systems and affects their grid-connectivity. Summary of the Invention

[0005] This application provides a valve position command generation method and apparatus to address the shortcomings of the prior art in which valve characteristics are oversimplified.

[0006] This application provides a valve position command generation method, including the following steps: Construct valve models, heat exchanger models, and turbine models; the valve model is used to characterize the functional relationship between the mass flow rate of air flowing through the valve and the valve position and the pressure difference across the valve; the heat exchanger model is used to characterize the changes in the thermodynamic state of air in the heat exchanger; the turbine model is used to characterize the expansion work capacity and thermodynamic state changes of air in the turbine. Based on steady-state operating conditions, for different gas storage conditions and valve positions, the mapping relationship between valve position and discharge power of the adiabatic compressed air energy storage system under different gas storage conditions is determined using the valve model, the heat exchanger model and the turbine model. Based on the mapping relationship, a valve position command is generated according to the current gas storage status and the feedforward power command; the valve position command is used to adjust the valve opening of the adiabatic compressed air energy storage system; the feedforward power command is used to characterize the power adjustment amount obtained by feedforward conversion of the primary frequency modulation deviation signal. Send the valve position command to the valve regulating device.

[0007] According to the valve position command generation method provided in this application, the valve model is represented as follows: in, This indicates the mass flow rate of air released from the gas storage facility; Indicates valve position; Indicates the speed of sound; This represents the density of a gas under standard conditions. This indicates the air pressure located upstream of the valve in the gas storage tank; Indicates the gas temperature under standard conditions; This indicates the air temperature located at the valve in the gas storage tank; This indicates the air pressure located downstream of the valve in the gas storage tank; Indicates the valve's opening pressure; Indicates the critical back pressure ratio; This indicates the subsonic speed index.

[0008] According to the valve position command generation method provided in this application, the heat exchanger model is represented as follows: in, This represents the inlet temperature of the j-th stage heat exchanger; This represents the outlet temperature of the j-th stage heat exchanger; This represents the heat exchange efficiency of the j-th stage heat exchanger; Indicates the temperature of the high-temperature heat transfer oil; This represents the outlet gas pressure of the j-th stage heat exchanger. This represents the inlet air pressure of the j-th stage heat exchanger.

[0009] According to the valve position command generation method provided in this application, the turbine model is represented as follows: in, This indicates the discharge power of the adiabatic compressed air energy storage system; Indicates the mechanical efficiency of the generator; This indicates the mass flow rate of air released from the gas storage facility; This represents the specific heat capacity of air at constant pressure. This represents the isentropic efficiency of the j-th stage turbine; This represents the intake temperature of the j-th stage turbine; This represents the expansion ratio of the j-th stage turbine; This represents the outlet gas temperature of the j-th turbine. This represents the outlet gas pressure of the j-th stage turbine; This represents the intake pressure of the j-th stage turbine; The adiabatic index indicates the thermal conductivity of air. This represents the total number of stages in the turbine.

[0010] According to the valve position command generation method provided in this application, the steady-state operating condition is that the outlet air pressure of the expansion subsystem of the adiabatic compressed air energy storage system is equal to the ambient atmospheric pressure. The expansion subsystem consists of a turbine, a heat exchanger, and a generator, and is used to convert the internal energy carried by the high-pressure air heated by the heat exchanger into mechanical energy.

[0011] According to the valve position command generation method provided in this application, the method, based on steady-state operating conditions and for different gas storage conditions and valve positions, utilizes the valve model, the heat exchanger model, and the turbine model to determine the mapping relationship between the valve position and the discharge power of the adiabatic compressed air energy storage system under different gas storage conditions, including: For each gas storage tank status and valve position, based on the assumed value of the inlet gas pressure of the expansion subsystem, the outlet gas pressure of the expansion subsystem is determined through the valve model, the heat exchanger model, and the turbine model. If the difference between the outlet pressure of the expansion subsystem and the ambient atmospheric pressure does not meet the preset convergence condition, adjust the inlet pressure of the expansion subsystem until the preset convergence condition is met. If the difference between the outlet air pressure of the expansion subsystem and the ambient atmospheric pressure satisfies the preset convergence condition, a mapping relationship is established between the discharge power of the adiabatic compressed air energy storage system calculated based on the current assumptions and the current valve position.

[0012] According to the valve position command generation method provided in this application, adjusting the inlet air pressure of the expansion subsystem includes: If the outlet pressure of the expansion subsystem is lower than the ambient atmospheric pressure, increase the inlet pressure of the expansion subsystem. If the outlet pressure of the expansion subsystem is greater than or equal to the ambient atmospheric pressure, the inlet pressure of the expansion subsystem shall be reduced.

[0013] According to the valve position command generation method provided in this application, the step of generating the valve position command based on the mapping relationship, according to the current gas storage state and the feedforward power command, includes: Obtain the current gas storage status and the feedforward power command; Based on the mapping relationship, the corresponding valve position correction amount is determined according to the current gas storage state and the feedforward power command; the valve position correction amount is used to characterize the valve opening change required in response to the feedforward power command under the current gas storage state. The valve position command is generated based on the valve position correction amount.

[0014] According to the valve position command generation method provided in this application, the step of generating the valve position command based on the valve position correction amount includes: Obtain the valve position base value; the valve position base value refers to the basic component constituting the valve position command. The valve position correction amount and the valve position base value are superimposed; The superimposed valve positions are subjected to speed and amplitude limiting processing to obtain the valve position command.

[0015] This application also provides a valve position command generation device, including the following modules: The module is used to build valve models, heat exchanger models, and turbine models. The valve model is used to characterize the functional relationship between the mass flow rate of air flowing through the valve and the valve position and the pressure difference across the valve. The heat exchanger model is used to characterize the changes in the thermodynamic state of air in the heat exchanger. The turbine model is used to characterize the expansion work capacity and thermodynamic state changes of air in the turbine. The determination module is used to determine the mapping relationship between the valve position and the discharge power of the adiabatic compressed air energy storage system under different gas storage conditions, based on steady-state operating conditions and for different gas storage states and valve positions, using the valve model, the heat exchanger model and the turbine model. The generation module is used to generate a valve position command based on the mapping relationship, the current gas storage state, and the feedforward power command; the valve position command is used to adjust the valve opening of the adiabatic compressed air energy storage system; the feedforward power command is used to characterize the power adjustment amount obtained by feedforward conversion of the primary frequency modulation deviation signal. The sending module is used to send the valve position command to the valve regulating device.

[0016] According to the valve position command generation device provided in this application, the valve model is represented as follows: in, This indicates the mass flow rate of air released from the gas storage facility; Indicates valve position; Indicates the speed of sound conductance; This represents the gas density under standard conditions. This indicates the air pressure located upstream of the valve in the gas storage tank; Indicates the gas temperature under standard conditions; This indicates the air temperature located at the valve in the gas storage tank; This indicates the air pressure located downstream of the valve in the gas storage tank; Indicates the valve's opening pressure; Indicates the critical back pressure ratio; This indicates the subsonic speed index.

[0017] According to a valve position command generation device provided in this application, the heat exchanger model is represented as follows: in, This represents the inlet temperature of the j-th stage heat exchanger; This represents the outlet temperature of the j-th stage heat exchanger; This represents the heat exchange efficiency of the j-th stage heat exchanger; Indicates the temperature of the high-temperature heat transfer oil; This represents the outlet gas pressure of the j-th stage heat exchanger. This represents the inlet air pressure of the j-th stage heat exchanger.

[0018] This application also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the valve position instruction generation method as described above.

[0019] This application also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the valve position instruction generation method as described above.

[0020] This application also provides a computer program product, including a computer program that, when executed by a processor, implements the valve position instruction generation method as described above.

[0021] The valve position command generation method and apparatus provided in this application construct a valve model that characterizes the functional relationship between the mass flow rate of air flowing through the valve and the valve position and the pressure difference across the valve. Combined with a heat exchanger model and a turbine model, the mapping relationship between valve position and discharge power under different gas storage conditions is determined based on steady-state operating conditions. This ensures that the correspondence between valve position and discharge power accurately reflects the comprehensive impact of valve characteristics on system power. Furthermore, based on the current gas storage state and feedforward power command, a valve position command is generated according to this mapping relationship. This allows the generated valve position command to accurately match the target discharge power requirement under different gas storage states, thereby improving the accuracy of valve position adjustment and the precision of power control in the adiabatic compressed air energy storage system, and enhancing the friendliness of the adiabatic compressed air energy storage system's interaction with the power grid. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a flowchart illustrating a valve position command generation method provided in this application.

[0024] Figure 2 This is a schematic diagram illustrating the mapping relationship between valve position and discharge power provided in this application.

[0025] Figure 3 This is a flowchart illustrating a valve position command generation method provided in this application.

[0026] Figure 4 This is a schematic diagram of a valve position command generation device provided in this application.

[0027] Figure 5 This is a schematic diagram of the structure of an electronic device provided in this application. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0029] The following is combined Figures 1 to 5The valve position command generation method and apparatus provided in the embodiments of this application are described.

[0030] Figure 1 This is a flowchart illustrating a valve position command generation method provided in this application, as shown below. Figure 1 As shown, the method includes the following steps S101-S104.

[0031] S101, construct the valve model, heat exchanger model, and turbine model.

[0032] This step aims to establish a mathematical model of the core components on the discharge side of the adiabatic compressed air energy storage system. Specifically, valve models, heat exchanger models, and turbine models are constructed to simulate the complete thermodynamic process of high-pressure air being released from the storage tank, heated by the heat exchanger, and finally expanding and doing work in the turbine. The construction of each model is described in detail below.

[0033] 1. Valve Model Construction During discharge in an adiabatic compressed air energy storage system, high-pressure air is released from the storage tank and enters the expansion subsystem to generate electricity. In actual operation, the discharge power (also known as the power generation power) can be controlled by adjusting the valve opening. Therefore, it is first necessary to construct a valve model that accurately reflects the valve flow characteristics. This valve model is used to characterize the functional relationship between the mass flow rate of air flowing through the valve and the valve position and the pressure difference across the valve.

[0034] The expansion subsystem consists of a turbine, a heat exchanger, and a generator. Its core function is to convert the internal energy carried by the high-pressure air heated by the heat exchanger into mechanical energy, which then drives the generator to output electrical energy. The inlet of the expansion subsystem is connected to the gas storage tank via a valve, and its outlet is directly open to the atmosphere.

[0035] As an exemplary implementation, the valve model can be represented by the following formula (1): (1) In formula (1), This indicates the mass flow rate of air released from the gas storage facility; Indicates valve position. It is a dimensionless quantity, and its range of values ​​can be... , The value can reflect the valve opening degree; Indicates the speed of sound conductance; This represents the gas density under standard conditions, and its value can be 1.185 kg / m³. This indicates the air pressure at the valve in the gas storage tank, which is also the air pressure at the upstream end of the valve. It is referred to as the gas storage tank pressure below. This represents the gas temperature under standard conditions, and its value can be 293.15 K. This indicates the air temperature located at the valve in the gas storage facility, hereinafter referred to as the gas storage temperature; This represents the inlet air pressure of the expansion subsystem for adiabatic compressed air energy storage, and is also the air pressure located downstream of the valve. Indicates the valve's opening pressure; Indicates the critical back pressure ratio; This indicates the subsonic speed index.

[0036] It should be noted that among the parameters mentioned above, the sound velocity conductivity... Valve opening pressure Critical back pressure ratio and subsonic index These are all characteristic parameters related to the specific valve structure. Once the valve model and structure are determined, the sound velocity and conductance... Valve opening pressure Critical back pressure ratio and subsonic index It can be determined through routine experiments, or calculated according to the relevant methods provided in GB / T 13513 standard.

[0037] 2. Construction of the heat exchanger model After high-pressure air flows through the valve, it needs to be heated by heat exchangers arranged before each stage of the turbine before it can expand and do work. After the air flows through the j-th stage heat exchanger, the change in air temperature can be expressed by the following formula (2), and the change in air pressure can be expressed by the following formula (3). Formulas (2) and (3) together constitute the heat exchanger model, which is used to characterize the change in the thermodynamic state of air in the heat exchanger.

[0038] (2) (3) In formulas (2) and (3), This represents the inlet temperature of the j-th stage heat exchanger; This represents the outlet temperature of the j-th stage heat exchanger; This represents the heat exchange efficiency of the j-th stage heat exchanger; Indicates the temperature of the high-temperature heat transfer oil; This represents the outlet gas pressure of the j-th stage heat exchanger. This represents the inlet air pressure of the j-th stage heat exchanger.

[0039] Based on this, for the adiabatic compressed air energy storage system in this embodiment, the inlet air pressure of its expansion subsystem is... equal to the inlet gas pressure of the first-stage heat exchanger This relationship can be expressed as the following formula (4).

[0040] (4) 3. Construction of the turbine model High-pressure air, heated by a heat exchanger, enters each stage of the turbine. Through the expansion process, it drives the turbine to rotate, thereby driving the generator to generate electricity. The turbine model is used to characterize the expansion work capacity and thermodynamic state changes of air in the turbine. Specifically, the discharge power of the entire expansion subsystem can be expressed by the following formula (5). For the j-th stage turbine, after the air expands and does work, its outlet temperature can be expressed by the following formula (6), and its outlet pressure can be expressed by the following formula (7). Formulas (5), (6), and (7) together constitute the turbine model.

[0041] (5) (6) (7) In formulas (5), (6), and (7), This indicates the discharge power of the adiabatic compressed air energy storage system; Indicates the mechanical efficiency of the generator; The mass flow rate of air released in the gas storage can be determined by formula (1); This represents the specific heat capacity of air at constant pressure. This represents the isentropic efficiency of the j-th stage turbine; This represents the intake air temperature of the j-th stage turbine. This represents the expansion ratio of the j-th stage turbine; This represents the outlet gas temperature of the j-th stage turbine. This represents the outlet gas pressure of the j-th stage turbine; This represents the intake pressure of the j-th stage turbine; The adiabatic index indicates the thermal conductivity of air. This represents the total number of stages in the turbine.

[0042] For the adiabatic compressed air energy storage system in this application embodiment, the outlet air pressure of its expansion subsystem is the last stage (the first stage). The outlet pressure of the turbine (stage) can be expressed by the following formula (8).

[0043] (8) in, This indicates the outlet pressure of the expansion subsystem.

[0044] S102, based on steady-state operating conditions, uses valve models, heat exchanger models, and turbine models to determine the mapping relationship between valve position and discharge power of the adiabatic compressed air energy storage system under different gas storage conditions and valve positions.

[0045] The status of a gas storage facility can include its pressure and temperature.

[0046] In one example, the steady-state operating condition can be: the outlet pressure of the expansion subsystem of the adiabatic compressed air energy storage system is equal to the ambient atmospheric pressure. As an exemplary implementation, the steady-state operating condition can be expressed by the following formula (9): (9) in, This indicates the outlet pressure of the expansion subsystem. It indicates the ambient atmospheric pressure.

[0047] In one example, for each gas storage unit state and valve position, the outlet pressure of the expansion subsystem can be determined based on the assumed inlet pressure of the expansion subsystem using valve, heat exchanger, and turbine models. If the difference between the outlet pressure of the expansion subsystem and the ambient atmospheric pressure does not meet the preset convergence condition, the inlet pressure of the expansion subsystem can be adjusted until the preset convergence condition is met. If the difference between the outlet pressure of the expansion subsystem and the ambient atmospheric pressure meets the preset convergence condition, a mapping relationship can be established based on the discharge power of the adiabatic compressed air energy storage system calculated under the current assumptions and the current valve position.

[0048] In one example, whether the difference between the outlet pressure of the expansion subsystem and the ambient atmospheric pressure satisfies the preset convergence condition can be determined by... To determine, among which, For example, a preset convergence threshold. It can be 0.1. Specifically, in Under these circumstances, it can be determined that the difference between the outlet pressure of the expansion subsystem and the ambient atmospheric pressure satisfies the preset convergence condition. In this case, it can be determined that the difference between the outlet pressure of the expansion subsystem and the ambient atmospheric pressure does not meet the preset convergence condition.

[0049] In one example, the above-mentioned adjustment of the inlet pressure of the expansion subsystem can be implemented as follows: when the outlet pressure of the expansion subsystem is less than the ambient atmospheric pressure, the inlet pressure of the expansion subsystem can be increased; when the outlet pressure of the expansion subsystem is greater than or equal to the ambient atmospheric pressure, the inlet pressure of the expansion subsystem can be decreased.

[0050] In one example, a dichotomy method can be used to adjust the inlet pressure of the expansion subsystem. Specifically: if the outlet pressure of the expansion subsystem is lower than the ambient atmospheric pressure, it indicates that the currently assumed inlet pressure of the expansion subsystem is too low. The inlet pressure can be updated to the midpoint between the current inlet pressure of the expansion subsystem and the gas storage pressure, thereby increasing the inlet pressure of the expansion subsystem. If the outlet pressure of the expansion subsystem is greater than or equal to the ambient atmospheric pressure, it indicates that the currently assumed inlet pressure of the expansion subsystem is too high. The inlet pressure can be updated to half of the current inlet pressure of the expansion subsystem, thereby decreasing the inlet pressure of the expansion subsystem.

[0051] The following is adopted Determine whether the difference between the outlet pressure of the expansion subsystem and the ambient atmospheric pressure meets the preset convergence condition, and The value is equal to 0.1, and the assumed value for the inlet gas pressure of the expansion subsystem is 0.5. Taking this application as an example, a detailed description of a process for determining the mapping relationship between valve position and discharge power under different gas storage conditions based on the dichotomy method is provided in the embodiments of this application. The method includes the following steps S201-S211.

[0052] S201, Under the current gas storage condition and valve position, assume the inlet gas pressure of the expansion subsystem is... Equals 0.5 .

[0053] S202, the current expansion subsystem inlet pressure The value is assigned to the auxiliary variable .

[0054] S203, input the current inlet air pressure of the expansion subsystem into the valve model to obtain the corresponding air mass flow rate. Based on the heat exchanger model and turbine model, the outlet gas pressure of the expansion subsystem is obtained. .

[0055] S204, according to Determine the outlet pressure of the expansion subsystem. Does the steady-state operating condition meet? If not, execute S205; if it does, execute S208.

[0056] S205, according to Determine the inlet pressure of the expansion subsystem Is the value too small? If it is satisfied, then execute S206; otherwise, execute S207.

[0057] S206, according to formula Update the inlet pressure of the expansion subsystem And execute S202.

[0058] S207, according to formula Update the inlet pressure of the expansion subsystem And execute S202.

[0059] S208, based on the heat exchanger model and turbine model, determines the discharge power of the adiabatic compressed air energy storage system. .

[0060] S209, Establishing the discharge power of the adiabatic compressed air energy storage system The mapping relationship between the valve position and the valve position.

[0061] S210: Check if all combinations of gas storage tank status and valve position have been executed. If yes, execute S211; otherwise, execute S201.

[0062] S211, End.

[0063] Figure 2 This is a schematic diagram illustrating the mapping relationship between valve position and discharge power in a certain gas storage state, as provided in an embodiment of this application.

[0064] Through the iterative solution process based on steady-state operating conditions described above, the mapping relationship between valve position and discharge power under different gas storage conditions can be accurately established. This mapping relationship fully reflects the combined influence of valve characteristics, heat exchanger characteristics, and turbine characteristics on the system discharge power, providing a reliable basis for subsequently generating accurate valve position commands.

[0065] S103 generates valve position commands based on the mapping relationship, the current gas storage status, and the feedforward power command.

[0066] S104, send the valve position command to the valve regulating device.

[0067] After establishing the mapping relationship between valve position and discharge power under different gas storage conditions through S102, the mapping relationship can be used in actual operation to generate valve position commands for adjusting the valve opening of the adiabatic compressed air energy storage system based on the current gas storage condition and feedforward power command.

[0068] The valve position command is used to adjust the valve opening of the adiabatic compressed air energy storage system, thereby achieving precise control of the system's discharge power. The feedforward power command characterizes the power regulation obtained from the primary frequency modulation deviation signal after feedforward conversion. The feedforward power command can be used to trigger the feedforward control loop for rapid power response. The value of the feedforward power command reflects the additional or reduced discharge power required by the adiabatic compressed air energy storage system in response to grid frequency fluctuations.

[0069] In one example, the above-mentioned generation of valve position commands based on the mapping relationship, according to the current gas storage state and feedforward power command, can be implemented as follows: obtain the current gas storage state and feedforward power command, determine the corresponding valve position correction amount based on the mapping relationship and the current gas storage state and feedforward power command, and generate valve position commands based on the valve position correction amount.

[0070] Valve position correction is used to characterize the amount of valve opening change required in response to feedforward power commands under the current gas storage conditions.

[0071] In one example, the above-mentioned generation of valve position command based on valve position correction amount can be implemented as follows: obtaining valve position base value; valve position base value refers to the basic component that constitutes valve position command, and the valve position correction amount and valve position base value are superimposed; the superimposed valve position is subjected to speed limiting and amplitude limiting processing to obtain valve position command.

[0072] The generation of the aforementioned valve position command can be achieved within the improved primary and secondary frequency regulation control framework for adiabatic compressed air energy storage. This improved control framework is formed by embedding the mapping relationship established through S102 as a power-valve position mapping link into the feedforward control loop, based on the traditional primary and secondary frequency regulation control framework that combines proportional-integral (PI) and feedforward control.

[0073] In terms of control loop structure, the improved control framework can include a PI control loop and a feedforward control loop. The PI control loop is used to achieve steady-state tracking of Automatic Generation Control (AGC) commands and primary frequency regulation commands, and can control overshoot and reduce oscillations by setting a PI limiting element. The feedforward control loop is used to achieve rapid action of primary frequency regulation of adiabatic compressed air storage, quickly adjusting the output power of the adiabatic compressed air storage. By embedding a power-valve position mapping element into the feedforward control loop, the feedforward control loop can flexibly adjust the valve position correction command according to the feedforward power command and the current storage state, thereby effectively reducing the overshoot of adiabatic compressed air storage during frequency response.

[0074] Based on the above control framework, the specific process for generating valve position commands can include: Figure 3 The content shown: Participation Figure 3 As shown, in the PI control loop, the grid frequency deviation First, it undergoes frequency dead zone filtering, then it passes through the droop coefficient. The conversion and primary frequency modulation (FM) limiting constraints are performed to generate the primary FM command. The AGC command issued by the dispatcher is then executed. First, the load change rate is limited by a command speed limiter, then superimposed with a primary frequency regulation command. The superimposed command, after passing through a power speed limiter to constrain the power change rate, yields a reference value for the discharge power. This reference value is then compared with the actual discharge power. After obtaining the power deviation by subtraction, the power deviation can be input into the PI controller to complete the integral-proportional calculation. After the output signal is limited and the integral is saturated by the PI controller, the valve position base value is obtained.

[0075] In the feedforward control loop, the grid frequency deviation After one frequency modulation dead zone filter, the signal is fed into the feedforward branch. Figure 3 (The part marked with a dashed line in the middle), through the feedforward coefficient After conversion, it becomes a feedforward power command. Then, the feedforward power command and the current gas storage status (including gas storage pressure) can be used. and gas storage temperature ), and the actual valve position The input power-valve position mapping circuit processes the data and outputs a valve position correction command. This valve position correction command is then converted into a usable valve position correction command after being constrained by feedforward limiting.

[0076] Then, the valve position base value and the valve position correction command can be superimposed, and after valve position speed limiting and valve position amplitude limiting constraints (i.e., speed limiting and amplitude limiting processing) are applied, the valve position command can be obtained. .

[0077] After generating the valve position command in the above manner, the valve position command can be sent to the valve regulating device, which can then adjust the opening degree of the adiabatic compressed air energy storage valve.

[0078] Through the above steps, this embodiment of the application can embed the power-valve position mapping link into the feedforward control loop, forming an improved primary and secondary frequency regulation control framework. After this improvement, the feedforward control loop can directly determine the corresponding valve position correction amount based on the feedforward power command and the current gas storage state through the mapping relationship, instead of relying on a fixed feedforward coefficient for coarse adjustment. This makes the feedforward control action more precise, effectively reduces the overshoot in the frequency response process of adiabatic compressed air energy storage, and ensures the speed of response, thereby significantly improving the friendliness of adiabatic compressed air energy storage in interacting with the power grid.

[0079] As described above, this application provides a method for generating valve position commands for adiabatic compressed air energy storage that considers valve characteristics. Based on valve characteristics and steady-state operating conditions, this method accurately determines the mapping relationship between discharge power and valve position under different gas storage conditions by jointly solving the valve model, heat exchanger model, and turbine model, providing an accurate basis for generating valve position commands. Furthermore, the power-valve position mapping relationship is embedded into the feedforward control loop, improving the existing adiabatic compressed air energy storage control framework. This allows the system to flexibly and accurately generate valve position correction commands based on the current gas storage state and feedforward power commands, effectively reducing overshoot during frequency response and improving the response quality when adiabatic compressed air energy storage provides frequency regulation services.

[0080] The valve position command generation device provided in this application is described below. The valve position command generation device described below can be referred to in correspondence with the valve position command generation method described above.

[0081] Figure 4 This is a schematic diagram of a valve position command generation device provided in an embodiment of this application, with reference to... Figure 4 As shown, the device includes: Module 401 is used to construct a valve model, a heat exchanger model, and a turbine model. The valve model is used to characterize the functional relationship between the mass flow rate of air flowing through the valve and the valve position and the pressure difference across the valve. The heat exchanger model is used to characterize the changes in the thermodynamic state of air in the heat exchanger. The turbine model is used to characterize the expansion work capacity and thermodynamic state changes of air in the turbine.

[0082] The determination module 402 is used to determine the mapping relationship between the valve position and the discharge power of the adiabatic compressed air energy storage system under different gas storage conditions, based on steady-state operating conditions and for different gas storage states and valve positions, using the valve model, the heat exchanger model and the turbine model.

[0083] The generation module 403 is used to generate a valve position command based on the mapping relationship, the current gas storage state, and the feedforward power command; the valve position command is used to adjust the valve opening of the adiabatic compressed air energy storage system; the feedforward power command is used to characterize the power adjustment amount obtained by feedforward conversion of the primary frequency modulation deviation signal.

[0084] The sending module 404 is used to send the valve position command to the valve regulating device.

[0085] Figure 5 An example is a schematic diagram of the physical structure of an electronic device, such as... Figure 5As shown, the electronic device may include: a processor 510, a communications interface 520, a memory 530, and a communication bus 540, wherein the processor 510, the communications interface 520, and the memory 530 communicate with each other via the communication bus 540. The processor 510 can call logical instructions in the memory 530 to execute a valve position instruction generation method, which includes: A valve model, a heat exchanger model, and a turbine model are constructed. The valve model represents the functional relationship between the air mass flow rate through the valve and the valve position and the pressure difference across the valve. The heat exchanger model represents the changes in the thermodynamic state of air in the heat exchanger. The turbine model represents the expansion work capacity and thermodynamic state changes of air in the turbine. Based on steady-state operating conditions, for different gas storage conditions and valve positions, the valve model, the heat exchanger model, and the turbine model are used to determine the mapping relationship between the valve position and the discharge power of the adiabatic compressed air energy storage system under different gas storage conditions. Based on the mapping relationship, a valve position command is generated according to the current gas storage condition and the feedforward power command. The valve position command is used to adjust the valve opening of the adiabatic compressed air energy storage system. The feedforward power command represents the power adjustment amount obtained by feedforward conversion of the primary frequency modulation deviation signal. The valve position command is sent to the valve adjustment device.

[0086] Furthermore, the logical instructions in the aforementioned memory 530 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0087] On the other hand, this application also provides a computer program product, which includes a computer program that can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer is able to execute the valve position instruction generation method provided by the above methods, the method including: A valve model, a heat exchanger model, and a turbine model are constructed. The valve model represents the functional relationship between the air mass flow rate through the valve and the valve position and the pressure difference across the valve. The heat exchanger model represents the changes in the thermodynamic state of air in the heat exchanger. The turbine model represents the expansion work capacity and thermodynamic state changes of air in the turbine. Based on steady-state operating conditions, for different gas storage conditions and valve positions, the valve model, the heat exchanger model, and the turbine model are used to determine the mapping relationship between the valve position and the discharge power of the adiabatic compressed air energy storage system under different gas storage conditions. Based on the mapping relationship, a valve position command is generated according to the current gas storage condition and the feedforward power command. The valve position command is used to adjust the valve opening of the adiabatic compressed air energy storage system. The feedforward power command represents the power adjustment amount obtained by feedforward conversion of the primary frequency modulation deviation signal. The valve position command is sent to the valve adjustment device.

[0088] Furthermore, this application also provides a non-transitory computer-readable storage medium storing a computer program thereon, which, when executed by a processor, is implemented to perform the valve position instruction generation method provided by the methods described above, the method comprising: A valve model, a heat exchanger model, and a turbine model are constructed. The valve model represents the functional relationship between the air mass flow rate through the valve and the valve position and the pressure difference across the valve. The heat exchanger model represents the changes in the thermodynamic state of air in the heat exchanger. The turbine model represents the expansion work capacity and thermodynamic state changes of air in the turbine. Based on steady-state operating conditions, for different gas storage conditions and valve positions, the valve model, the heat exchanger model, and the turbine model are used to determine the mapping relationship between the valve position and the discharge power of the adiabatic compressed air energy storage system under different gas storage conditions. Based on the mapping relationship, a valve position command is generated according to the current gas storage condition and the feedforward power command. The valve position command is used to adjust the valve opening of the adiabatic compressed air energy storage system. The feedforward power command represents the power adjustment amount obtained by feedforward conversion of the primary frequency modulation deviation signal. The valve position command is sent to the valve adjustment device.

[0089] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0090] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0091] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A method for generating valve position commands, characterized in that, The method includes: Construct valve models, heat exchanger models, and turbine models; the valve model is used to characterize the functional relationship between the mass flow rate of air flowing through the valve and the valve position and the pressure difference across the valve; the heat exchanger model is used to characterize the changes in the thermodynamic state of air in the heat exchanger; the turbine model is used to characterize the expansion work capacity and thermodynamic state changes of air in the turbine. Based on steady-state operating conditions, for different gas storage conditions and valve positions, the mapping relationship between valve position and discharge power of the adiabatic compressed air energy storage system under different gas storage conditions is determined using the valve model, the heat exchanger model and the turbine model. Based on the mapping relationship, a valve position command is generated according to the current gas storage status and the feedforward power command; the valve position command is used to adjust the valve opening of the adiabatic compressed air energy storage system; the feedforward power command is used to characterize the power adjustment amount obtained by feedforward conversion of the primary frequency modulation deviation signal. Send the valve position command to the valve regulating device.

2. The valve position command generation method according to claim 1, characterized in that, The valve model is represented as follows: in, This indicates the mass flow rate of air released from the gas storage facility; Indicates valve position; Indicates the speed of sound conductance; This represents the gas density under standard conditions. This indicates the air pressure located upstream of the valve in the gas storage tank; Indicates the gas temperature under standard conditions; This indicates the air temperature located at the valve in the gas storage tank; This indicates the air pressure located downstream of the valve in the gas storage tank; Indicates the valve's opening pressure; Indicates the critical back pressure ratio; This indicates the subsonic speed index.

3. The valve position command generation method according to claim 1, characterized in that, The heat exchanger model is represented as follows: in, This represents the inlet temperature of the j-th stage heat exchanger; This represents the outlet temperature of the j-th stage heat exchanger; This represents the heat exchange efficiency of the j-th stage heat exchanger; Indicates the temperature of the high-temperature heat transfer oil; This represents the outlet gas pressure of the j-th stage heat exchanger. This represents the inlet air pressure of the j-th stage heat exchanger.

4. The valve position command generation method according to claim 1, characterized in that, The turbine model is represented as follows: in, This indicates the discharge power of the adiabatic compressed air energy storage system; Indicates the mechanical efficiency of the generator; This indicates the mass flow rate of air released from the gas storage facility; This represents the specific heat capacity of air at constant pressure. This represents the isentropic efficiency of the j-th stage turbine; This represents the intake temperature of the j-th stage turbine; This represents the expansion ratio of the j-th stage turbine; This represents the outlet gas temperature of the j-th turbine. This represents the outlet gas pressure of the j-th stage turbine; This represents the intake pressure of the j-th stage turbine; The adiabatic index indicates the thermal conductivity of air. This represents the total number of stages in the turbine.

5. The valve position command generation method according to any one of claims 1-4, characterized in that, The steady-state operating conditions are as follows: the outlet air pressure of the expansion subsystem of the adiabatic compressed air energy storage system is equal to the ambient atmospheric pressure; the expansion subsystem consists of a turbine, a heat exchanger and a generator, and is used to convert the internal energy carried by the high-pressure air heated by the heat exchanger into mechanical energy.

6. The valve position command generation method according to claim 5, characterized in that, Based on steady-state operating conditions, and considering different gas storage conditions and valve positions, the mapping relationship between valve positions and the discharge power of the adiabatic compressed air energy storage system under different gas storage conditions is determined using the valve model, the heat exchanger model, and the turbine model. This includes: For each gas storage tank status and valve position, based on the assumed value of the inlet gas pressure of the expansion subsystem, the outlet gas pressure of the expansion subsystem is determined through the valve model, the heat exchanger model, and the turbine model. If the difference between the outlet pressure of the expansion subsystem and the ambient atmospheric pressure does not meet the preset convergence condition, adjust the inlet pressure of the expansion subsystem until the preset convergence condition is met. If the difference between the outlet air pressure of the expansion subsystem and the ambient atmospheric pressure satisfies the preset convergence condition, a mapping relationship is established between the discharge power of the adiabatic compressed air energy storage system calculated based on the current assumptions and the current valve position.

7. The valve position command generation method according to claim 6, characterized in that, Adjusting the inlet pressure of the expansion subsystem includes: If the outlet pressure of the expansion subsystem is lower than the ambient atmospheric pressure, increase the inlet pressure of the expansion subsystem. If the outlet pressure of the expansion subsystem is greater than or equal to the ambient atmospheric pressure, the inlet pressure of the expansion subsystem shall be reduced.

8. The valve position command generation method according to any one of claims 1-4, characterized in that, The process of generating valve position commands based on the mapping relationship, according to the current gas storage status and feedforward power commands, includes: Obtain the current gas storage status and the feedforward power command; Based on the mapping relationship, the corresponding valve position correction amount is determined according to the current gas storage state and the feedforward power command; the valve position correction amount is used to characterize the valve opening change required in response to the feedforward power command under the current gas storage state. The valve position command is generated based on the valve position correction amount.

9. The valve position command generation method according to claim 8, characterized in that, The step of generating the valve position command based on the valve position correction amount includes: Obtain the valve position base value; the valve position base value refers to the basic component that constitutes the valve position command. The valve position correction amount and the valve position base value are superimposed; The superimposed valve positions are subjected to speed and amplitude limiting processing to obtain the valve position command.

10. A valve position command generation device, characterized in that, The device includes: The module is used to build valve models, heat exchanger models, and turbine models. The valve model is used to characterize the functional relationship between the mass flow rate of air flowing through the valve and the valve position and the pressure difference across the valve. The heat exchanger model is used to characterize the changes in the thermodynamic state of air in the heat exchanger. The turbine model is used to characterize the expansion work capacity and thermodynamic state changes of air in the turbine. The determination module is used to determine the mapping relationship between the valve position and the discharge power of the adiabatic compressed air energy storage system under different gas storage conditions, based on steady-state operating conditions and for different gas storage states and valve positions, using the valve model, the heat exchanger model and the turbine model. The generation module is used to generate a valve position command based on the mapping relationship, the current gas storage state, and the feedforward power command; the valve position command is used to adjust the valve opening of the adiabatic compressed air energy storage system; the feedforward power command is used to characterize the power adjustment amount obtained by feedforward conversion of the primary frequency modulation deviation signal. The sending module is used to send the valve position command to the valve regulating device.

11. The valve position command generation device according to claim 10, characterized in that, The valve model is represented as follows: in, This indicates the mass flow rate of air released from the gas storage facility; Indicates valve position; Indicates the speed of sound; This represents the density of a gas under standard conditions. This indicates the air pressure located upstream of the valve in the gas storage tank; Indicates the gas temperature under standard conditions; This indicates the air temperature located at the valve in the gas storage tank; This indicates the air pressure located downstream of the valve in the gas storage tank; Indicates the valve's opening pressure; Indicates the critical back pressure ratio; This indicates the subsonic speed index.

12. The valve position command generation device according to claim 10, characterized in that, The heat exchanger model is represented as follows: in, This represents the inlet temperature of the j-th stage heat exchanger; This represents the outlet temperature of the j-th stage heat exchanger; This represents the heat exchange efficiency of the j-th stage heat exchanger; Indicates the temperature of the high-temperature heat transfer oil; This represents the outlet gas pressure of the j-th stage heat exchanger. This represents the inlet air pressure of the j-th stage heat exchanger.

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