Compressed air energy storage power station turbine side phase modulation operation control method

Abstract

The invention relates to the technical field of compressed air energy storage, in particular to a compressed air energy storage power station turbine side phase modulation operation control method which comprises the steps that a multi-time-scale state space model of a compressed air energy storage power station turbine side is established; an optimization function of the phase modulation stage is determined according to the coupling relation between the heat compensation amount of the turbine side in the phase modulation stage and the turbine exhaust temperature; adding an auxiliary state variable to the multi-time scale state space model to form an augmented state space model, and generating a power tracking target function according to the optimization function and the augmented state space model; and deploying the power tracking target function in the MPC controller, predicting operation parameters of the turbine side at the next moment by using the power tracking target function, and realizing phase modulation operation of the turbine side based on the predicted operation parameters. Therefore, ultra-low-power-consumption phase modulation operation of the turbine side of the compressed air energy storage power station can be achieved, and long-time small-flow economical and stable phase modulation operation of a generator set on the turbine side of the compressed air energy storage power station can be achieved.

Description

Technical Field

[0001] The present application relates to the technical field of compressed air energy storage, and particularly to a control method for phase - modulation operation on the turbine side of a compressed air energy storage power station. Background Art

[0002] With the rapid increase in the penetration rate of new - energy power generation in the power system, the power grid gradually shows the characteristics of "double highs" (high proportion of renewable energy and high proportion of power - electronic devices), and its voltage stability and dynamic reactive - power support requirements have increased significantly. Although traditional synchronous phase - modifiers can provide reactive - power compensation, they have problems such as high construction costs and insufficient operation flexibility. CAES (Compressed Air Energy Storage) is one of the key technologies for large - scale long - term electrical - energy storage, and has flexible operation modes such as peak shaving, frequency modulation, phase modulation, and black start. During phase - modulation operation, the energy - storage power station is in an ultra - low - power - consumption state, and the turbine - generator set maintains a synchronous speed relying on the energy stored in the system itself. Currently, few control strategies comprehensively consider the influence of factors such as partial - load characteristics and heat - exchanger thermal inertia on the system's dynamic performance during the power - tracking control process, especially the control effect in the low - power range on the turbine side is not ideal.

[0003] To fully exploit the flexible phase - modulation operation potential of the compressed air energy storage power station, optimization and control means need to be adopted on the turbine side of the compressed air energy storage power station to ensure ultra - low - power - consumption economic phase - modulation operation on the turbine side. At present, there is a lack of relevant research on the phase - modulation operation control strategy for energy - storage power stations. On the one hand, it involves the stable operation control of the turbine unit with a small flow rate for a long time. On the other hand, since phase - modulation operation needs to rely on the kinetic energy of high - pressure air to overcome no - load losses, and the air consumption is approximately constant, there is a certain optimization space for the heat consumption during phase - modulation according to different requirements for exhaust - gas temperature and heat - supply methods. Summary of the Invention

[0004] The present application provides a control method for phase - modulation operation on the turbine side of a compressed air energy storage power station. This method can achieve ultra - low - power - consumption phase - modulation operation on the turbine side of the compressed air energy storage power station, and can enable the generator set on the turbine side of the compressed air energy storage power station to achieve long - time small - flow economic and stable phase - modulation operation.

[0005] An embodiment of the first aspect of the present application provides a method for controlling the phase - modulation operation on the turbine side of a compressed - air energy - storage power station, including the following steps: establishing a multi - time - scale state - space model of the turbine side of the compressed - air energy - storage power station; obtaining the coupling relationship between the heat supply and the turbine exhaust temperature during the phase - modulation stage, and determining the optimization function according to the coupling relationship; taking the thermal power required for the no - load loss of each - stage turbine generator set as an auxiliary state variable and adding it to the multi - time - scale state - space model to form an augmented state - space model, and generating a power - tracking objective function according to the optimization function and the augmented state - space model; deploying the power - tracking objective function in an MPC (Model Predictive Control) controller, and within each sampling time of the MPC controller, predicting the operating parameters of the turbine side at the next moment using the power - tracking objective function, and realizing the phase - modulation operation of the turbine side based on the predicted operating parameters.

[0006] Optionally, establishing a multi - time - scale state - space model of the turbine side of the compressed - air energy - storage power station includes: obtaining the volumes of the primary heat exchanger and the air pipeline on the turbine side of the energy - storage power station; reducing the volumes of the primary heat exchanger and the air pipeline to the volume link of the turbine cavity; taking the air mass flow rate at the outlet of the volume link as the state quantity, taking the inlet and outlet temperatures of the air side of the heat exchanger and the turbine speed as state variables, and taking the opening degrees of the throttle valve and the main turbine regulating valve and the mass flow rate of the high - temperature heat - transfer oil in the heat exchanger as control quantities, and establishing a multi - time - scale state - space model considering gas - volume inertia, heat - transfer inertia of the heat exchanger, and shaft - system mechanical inertia.

[0007] Optionally, the multi - time - scale state - space model includes a multi - variable coupling differential equation set, a steady - state thermodynamic characteristic model of the turbine subsystem, and a throttle - valve and main - turbine - regulating - valve group model, where the multi - variable coupling differential equation set is constructed based on the mass conservation of the turbine chamber and the law of energy conservation of heat exchange in the heat exchanger.

[0008] Optionally, obtaining the coupling relationship between the heat supply and the turbine exhaust temperature during the phase - modulation stage includes: obtaining the relationship between the mass flow rate of the heat - transfer oil and the turbine inlet temperature; calculating the total heat - supply power of the heat - transfer oil on the turbine side during the energy - release stage; analyzing the coupling relationship between the heat supply and the turbine exhaust temperature during the phase - modulation stage according to the relationship between the mass flow rate of the heat - transfer oil and the turbine inlet temperature and the total heat - supply power of the heat - transfer oil on the turbine side during the energy - release stage.

[0009] Optionally, the optimization function is:

[0010]

[0011] Where is the mass flow rate of the heat - transfer oil flowing through the i - th - stage heat exchanger during the phase - modulation stage; and are the temperatures of the high-pressure air entering and leaving the i-th stage heat exchanger, respectively; and are the temperatures of the heat-conducting oil entering and leaving the i-th stage heat exchanger, respectively; N g is the number of heat exchanger stages; c p,a is the specific heat capacity of air; is the mass flow rate of air flowing through the heat exchanger; c p,HTF is the specific heat capacity of the heat-conducting oil; s.t is the constraint condition.

[0012] Optionally, a power tracking objective function is generated according to the optimization function and the augmented state space model, and further includes: linearizing and discretizing the augmented state space model to obtain a simplified model; generating a power tracking objective function according to the optimization function and the simplified model.

[0013] Optionally, the simplified model is:

[0014]

[0015] where H, J, and G are transformed constant matrices; is the augmented state variable matrix; is the augmented state variable matrix at time step k + 1; is the augmented state variable matrix at time step k; k is the time step; is the control variable matrix at time step k; is the turbine output power at time step k.

[0016] Optionally, the power tracking objective function is:

[0017]

[0018] where is the augmented state variable matrix; is the control variable matrix; N is the number of turbine stages; is the thermal power required to overcome the no-load loss of the turbine generator set; rated power of the turbine generator set under no-load operation; is the optimization function.

[0019] The second aspect of the present application provides a phase - modulation operation control device for the turbine side of a compressed air energy storage power station, including: a building module for building a multi - time - scale state - space model of the turbine side of the compressed air energy storage power station; a determination module for obtaining the coupling relationship between the heat supply amount and the turbine exhaust temperature during the phase - modulation stage, and determining an optimization function according to the coupling relationship; a generation module for taking the thermal power required for the no - load loss of each - stage turbine generator set as an auxiliary state variable and adding it to the multi - time - scale state - space model to form an augmented state - space model, and generating a power - tracking objective function according to the optimization function and the augmented state - space model; a prediction module for deploying the power - tracking objective function in the MPC controller, and predicting the operating parameters of the turbine side at the next moment using the power - tracking objective function within each MPC controller sampling time, and realizing the phase - modulation operation of the turbine side based on the predicted operating parameters.

[0020] Optionally, the building module is further configured to: obtain the volumes of the primary heat exchanger and the air pipeline on the turbine side of the energy storage power station; reduce the volumes of the primary heat exchanger and the air pipeline to the volume link of the turbine cavity; take the air mass flow rate at the outlet of the volume link as the state quantity, take the inlet and outlet temperatures of the air side of the heat exchanger and the turbine speed as state variables, and take the throttle valve and the opening degrees of the main turbine regulating valves and the mass flow rate of the high - temperature heat - conducting oil in the heat exchanger as control quantities to build a multi - time - scale state - space model considering gas volume inertia, heat transfer inertia of the heat exchanger, and shaft - system mechanical inertia.

[0021] Optionally, the multi - time - scale state - space model includes a multi - variable coupled differential equation set, a steady - state thermodynamic characteristic model of the turbine subsystem, and a throttle valve and main turbine regulating valve group model, where the multi - variable coupled differential equation set is constructed based on the mass conservation of the turbine chamber and the law of energy conservation of heat exchange in the heat exchanger.

[0022] Optionally, the determination module is further configured to: obtain the relationship between the mass flow rate of the heat - conducting oil and the turbine inlet temperature; calculate the total heat supply power of the heat - conducting oil on the turbine side during the energy - release stage; analyze the coupling relationship between the heat supply amount and the turbine exhaust temperature on the turbine side during the phase - modulation stage according to the relationship between the mass flow rate of the heat - conducting oil and the turbine inlet temperature and the total heat supply power of the heat - conducting oil on the turbine side during the energy - release stage.

[0023] Optionally, the optimization function is:

[0024]

[0025] Where is the mass flow rate of the heat - conducting oil flowing through the i - th - stage heat exchanger during the phase - modulation stage; and are the temperatures of the high - pressure air entering and leaving the i - th - stage heat exchanger respectively; and are the temperatures of the heat transfer oil entering and leaving the i-th stage heat exchanger; N g is the number of stages of the heat exchanger; c p,a is the specific heat capacity of air; is the mass flow rate of air flowing through the heat exchanger; c p,HTF is the specific heat capacity of the heat transfer oil; s.t is the constraint condition.

[0026] Optionally, the generation module is further configured to: linearize and discretize the augmented state space model to obtain a simplified model; generate a power tracking objective function according to the optimization function and the simplified model.

[0027] Optionally, the simplified model is:

[0028]

[0029] wherein, H, J, and G are transformed constant matrices; is the augmented state variable matrix; is the augmented state variable matrix at time step k + 1; is the augmented state variable matrix at time step k; k is the time step; is the control variable at time step k; is the turbine output power at time step k. Matrix

[0030] Optionally, the power tracking objective function is:

[0031]

[0032] wherein, is the augmented state variable matrix is the control variable matrix; N is the number of stages of the turbine; is the thermal power required to overcome the no-load loss of the turbine generator set; rated power of the turbine generator set operating at no load; is the optimization function.

[0033] An embodiment of the third aspect of the present application provides an electronic device, including: a memory, a processor, and a computer program stored on the memory and executable on the processor, and the processor executes the program to perform the phase modulation operation control method for the turbine side of the compressed air energy storage power station as described in the above embodiment.

[0034] Thus, the present application has at least the following beneficial effects:

[0035] The embodiments of the present application can establish a multi-time scale state space model for the turbine side of a compressed air energy storage power station, consider the coupling relationship between the heat supplement amount and the turbine exhaust temperature during the phase modulation stage, and then determine the optimization function during the phase modulation stage according to the coupling relationship. On the premise of meeting the requirements of the turbine exhaust temperature, the usage amount of heat-conducting oil is minimized as much as possible, the energy consumption is reduced, and the thermal power required for the no-load loss of each stage of turbine generator set is used as an auxiliary state variable and added to the multi-time scale state space model to form an augmented state space model, further improving the description ability and control accuracy of the model. The power tracking objective function is generated through the optimization function and the augmented state space model, and the generated power tracking objective function is deployed in the MPC controller to predict the operating parameters at the next moment at each sampling time, and based on these predictions, phase modulation operation is realized, so that a fast and accurate response can be made in a complex dynamic environment, and then the turbine generator set on the turbine side is in an ultra-low power consumption operating state during the phase modulation stage, enabling the turbine generator set of the compressed air energy storage power station to achieve long-time and small-flow economic and stable phase modulation operation, and fully exploiting the operation potential of the compressed air energy storage power station.

[0036] Additional aspects and advantages of the present application will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present application. Brief Description of the Drawings

[0037] The above and / or additional aspects and advantages of the present application will become apparent and be readily understood from the following description of the embodiments in conjunction with the drawings, where:

[0038] Figure 1 is a flowchart of a phase modulation operation control method for the turbine side of a compressed air energy storage power station according to an embodiment of the present application;

[0039] Figure 2 is a schematic diagram of the phase modulation operation of a compressed air energy storage power station according to an embodiment of the present application;

[0040] Figure 3 is an example diagram of a phase modulation operation control device for the turbine side of a compressed air energy storage power station according to an embodiment of the present application;

[0041] Figure 4 is a schematic structural diagram of an electronic device according to an embodiment of the present application. Detailed Description of the Embodiments

[0042] The embodiments of the present application will be described in detail below. The examples of the embodiments are shown in the drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the drawings are exemplary and are intended to explain the present application and should not be construed as limiting the present application.

[0043] The phase - modulation operation control method for the turbine side of a compressed air energy storage power station according to an embodiment of the present application will be described below with reference to the accompanying drawings. In view of the lack of relevant research on the phase - modulation operation control strategy for energy storage power stations in the prior art mentioned in the above - mentioned background art. On the one hand, it involves the control of long - term stable operation of the turbine unit with small flow rates. On the other hand, since phase - modulation operation relies on the kinetic energy of high - pressure air to overcome no - load losses, and the air consumption is approximately constant, but there is a certain optimization space for the heat consumption of phase - modulation according to different requirements for exhaust gas temperature and heat - supplement methods. The present application provides a phase - modulation operation control method for the turbine side of a compressed air energy storage power station. In this method, a multi - time - scale state - space model of the turbine side of the compressed air energy storage power station can be established, considering the coupling relationship between the heat - supplement amount and the turbine exhaust gas temperature during the phase - modulation stage. Then, an optimization function for the phase - modulation stage is determined according to the coupling relationship. On the premise of meeting the requirements of the turbine exhaust gas temperature, the usage amount of heat - conducting oil is minimized as much as possible to reduce energy consumption. Moreover, the thermal power required for the no - load losses of each - stage turbine generator set is used as an auxiliary state variable and added to the multi - time - scale state - space model to form an augmented state - space model, further improving the description ability and control accuracy of the model. A power - tracking objective function is generated through the optimization function and the augmented state - space model, and the generated power - tracking objective function is deployed in the MPC controller. At each sampling time, the operating parameters at the next moment are predicted, and phase - modulation operation is realized based on these predictions. Thus, it can make a rapid and accurate response in a complex dynamic environment, and further achieve that the turbine - side generator set of the compressed air energy storage power station is in an ultra - low - power consumption operation state during the phase - modulation stage, enabling the turbine generator set of the compressed air energy storage power station to achieve long - term small - flow economic and stable phase - modulation operation and fully exploiting the operation potential of the compressed air energy storage power station.

[0044] Specifically, Figure 1 FIG. is a schematic flow chart of a phase - modulation operation control method for the turbine side of a compressed air energy storage power station provided by an embodiment of the present application.

[0045] As Figure 1 shown, the phase - modulation operation control method for the turbine side of the compressed air energy storage power station includes the following steps:

[0046] In step S101, a multi - time - scale state - space model of the turbine side of the compressed air energy storage power station is established.

[0047] It can be understood that an embodiment of the present application can establish a multi - time - scale state - space model of the turbine side of the compressed air energy storage power station for subsequent phase - modulation operation of the turbine side of the compressed air energy storage power station.

[0048] Among them, the phase modulation operation on the turbine side of the compressed air energy storage power station relies on the high-pressure air in the gas storage chamber to provide power (heat supplement is required when necessary) to keep the turbine generator set at a synchronous speed. During the phase modulation stage, the turbine generator set operates at an ultra-low power consumption state, and its exhaust mass flow rate is jointly regulated by the throttle valve and the turbine regulating valve. For large-capacity air turbines, in order to reduce thermal stress and prevent ice damage to the turbine blades caused by too low exhaust temperature, it is necessary to supplement heat to the air during the phase modulation stage to increase its temperature.

[0049] In the embodiment of the present application, a multi-time scale state space model of the turbine side of the compressed air energy storage power station is established, including: obtaining the volumes of the primary heat exchanger and the air pipeline on the turbine side of the energy storage power station; the volume reduction link of the primary heat exchanger and the air pipeline to the volume of the turbine cavity; taking the air mass flow rate at the outlet of the volume link as the state variable, taking the inlet and outlet temperatures of the air side of the heat exchanger and the turbine speed as the state variables, and taking the opening degrees of the throttle valve and the main turbine regulating valve and the mass flow rate of the high-temperature heat transfer oil in the heat exchanger as the control variables, a multi-time scale state space model considering gas volume inertia, heat exchanger heat transfer inertia and shaft system mechanical inertia is established.

[0050] Among them, the multi-time scale state space model includes a multi-variable coupling differential equation set, a steady-state thermodynamic characteristic model of the turbine subsystem, and a throttle valve and main turbine regulating valve group model. Among them, the multi-variable coupling differential equation set is constructed based on the mass conservation of the turbine chamber and the energy conservation law of heat exchange in the heat exchanger.

[0051] Since the expansion ratio and isentropic efficiency of the turbine can be determined by its inlet air mass flow rate and inlet temperature, and the components related to air flow regulation are mainly the throttle valve and the main turbine regulating valve group, it is possible to realize the long-term stable operation of the turbine generator set with a small flow rate by controlling the opening degrees of the throttle valve and the main turbine regulating valve group and the mass flow rate of the heat-carrying working medium in the heat exchanger. And under the phase modulation operation mode, the dynamic characteristics on the turbine side mainly consider the volume effect between each stage of the turbine and the gas transmission pipeline, the heat transfer time delay of the heat exchanger, etc. Therefore, the embodiment of the present application can be based on the mass conservation, energy conservation and angular momentum conservation combined with the component thermodynamic formula, taking the inlet and outlet temperatures of the air side of the heat exchanger, the turbine speed and the outlet air mass flow rate as the state variables, and taking the opening degrees of the throttle valve and the main turbine regulating valve and the mass flow rate of the high-temperature heat transfer oil in the heat exchanger as the control variables, to establish a multi-time scale state space model of the turbine side considering gas volume inertia, heat exchanger heat transfer inertia and shaft system mechanical inertia.

[0052] Specifically, the process of establishing the multi-time scale state space model in the embodiment of the present application is as follows:

[0053] Based on the mass conservation of the turbine chamber and the energy conservation law of heat exchange in the heat exchanger, the following multi-variable coupling differential equation set can be constructed:

[0054]

[0055] Among them, represents the mass flow rate at the outlet of the high-pressure turbine represents the mass flow rate at the inlet of the high-pressure volume section; represents the mass flow rate at the outlet of the low-pressure turbine, represents the mass flow rate at the inlet of the low-pressure volume section; T Ve T1 represents the high-pressure volume inertia time constant, T Ve T2 represents the high-pressure volume inertia time constant; VT1(t) is the temperature difference between the air inlet and outlet of the high-pressure heat exchanger, and VT2(t) represents the temperature difference between the air inlet and outlet of the low-pressure heat exchanger; T HS is the inlet temperature of the heat transfer oil of the heat exchanger, T AS is the high-pressure gas temperature at the outlet of the gas storage reservoir, is the temperature at the outlet of the high-pressure turbine; T HX,1 is the heat transfer delay of the high-pressure heat exchanger, T HX,2 is the heat transfer delay of the low-pressure heat exchanger; ε is the heat exchanger effectiveness; C min is the minimum value of the constant pressure specific heat of air and heat transfer oil.

[0056] The steady-state thermodynamic characteristic modeling of the turbine subsystem is as follows:

[0057]

[0058] Formulas (1.2)-(1.4) reflect the coupling relationship of the mass flow rate, temperature, and output heat power of the turbine. Among them, the isentropic efficiency coefficient of the turbine in formula (1.4) is obtained by fitting the simulation results or the equipment test curve.

[0059] The modeling of the throttle valve and the main control valve of the turbine is as follows:

[0060]

[0061] Among them, m TV is the flow rate through the valve; A TV represents the flow area and is a design parameter; is the inlet pressure of the valve; is the outlet pressure of the throttle valve; ρ is the air density; the resistance coefficient ξ is related to the flow area and the valve opening.

[0062] In step S102, obtain the coupling relationship between the heat supply amount and the turbine exhaust temperature on the turbine side, and determine the optimization function in the phase modulation stage according to the coupling relationship.

[0063] During the phase modulation operation, the heat supply directly affects the exhaust temperature of the turbine. If the heat supply is insufficient, the exhaust temperature of the turbine may be too low, resulting in equipment damage (such as ice damage to the turbine blades); if the heat supply is excessive, it will cause unnecessary energy waste. Therefore, the embodiments of the present application can obtain the coupling relationship between the heat supply and the exhaust temperature of the turbine side during the phase modulation stage, and determine the optimization function during the phase modulation stage according to the coupling relationship, so as to better control the phase modulation operation subsequently.

[0064] In the embodiments of the present application, obtaining the coupling relationship between the heat supply and the exhaust temperature of the turbine side during the phase modulation stage includes: obtaining the relationship between the mass flow rate of the heat transfer oil and the intake temperature of the turbine; calculating the total heat supply power of the heat transfer oil on the turbine side during the energy release stage; and analyzing the coupling relationship between the heat supply and the exhaust temperature of the turbine side during the phase modulation stage according to the relationship between the mass flow rate of the heat transfer oil and the intake temperature of the turbine, and the total heat supply power of the heat transfer oil on the turbine side during the energy release stage.

[0065] It can be understood that the embodiments of the present application can obtain the relationship between the mass of the heat transfer oil and the intake temperature of the turbine, calculate the total heat supply power of the heat transfer oil on the turbine side during the energy release stage, and then analyze the coupling relationship between the heat supply and the exhaust temperature of the turbine side during the phase modulation stage according to the relationship between the mass flow rate of the heat transfer oil and the intake temperature of the turbine, and the total heat supply power of the heat transfer oil on the turbine side during the energy release stage.

[0066] Specifically, when the heat transfer efficiency and the air mass flow rate are constant, adjusting can control the intake temperature of the turbine, thereby indirectly controlling the exhaust temperature of the turbine. The relationship between the mass flow rate of the heat transfer oil and the intake temperature of the turbine satisfies:

[0067]

[0068] At the same time, the total heat supply power of the heat transfer oil during the energy release stage can be calculated by the following formula:

[0069]

[0070] According to different requirements for the exhaust temperature of the turbine and the heat supply method, while ensuring that the exhaust temperature of the turbine is not too low, avoid overheating of the high and low pressure turbines, resulting in heat waste. Therefore, there is a certain optimization space for the heat consumption during phase modulation.

[0071] Analyze the coupling relationship between the heat supply and the exhaust temperature during the phase modulation stage, and propose the following optimization model, that is, the optimization function, with the goal of minimizing the total heat consumption during the phase modulation stage:

[0072]

[0073] Among them, $m_{i}$ is the mass flow rate of the heat-conducting oil flowing through the $i$-th stage heat exchanger during the phase modulation stage; and $T_{i,in}$ and $T_{i,out}$ are the temperatures of the high-pressure air entering and leaving the $i$-th stage heat exchanger, respectively; and $t_{i,in}$ and $t_{i,out}$ are the temperatures of the heat-conducting oil entering and leaving the $i$-th stage heat exchanger, respectively; $N$ g is the number of heat exchanger stages; $c_{p,a}$ p,a is the specific heat capacity of air; $m_{a}$ is the mass flow rate of the air flowing through the heat exchanger; $c_{p,o}$ p,HTF is the specific heat capacity of the heat-conducting oil; s.t is the constraint condition.

[0074] In step S103, the thermal power required for the no-load loss of each stage of the turbine generator set is added as an auxiliary state variable to the multi-time scale state space model to form an augmented state space model, and a power tracking objective function is generated according to the optimization function and the augmented state space model.

[0075] It can be understood that in the embodiment of the present application, the thermal power required for the no-load loss of each stage of the turbine generator set can be added as an auxiliary state vector to the multi-time scale state space model to form an augmented state space model, and a power tracking objective function is generated according to the optimization function and the augmented state space model, so as to better describe the behavior of the turbine side of the compressed air energy storage power station.

[0076] In the embodiment of the present application, generating a power tracking objective function according to the optimization function and the augmented state space model further includes: linearizing and discretizing the augmented state space model to obtain a simplified model; generating a power tracking objective function according to the optimization function and the simplified model.

[0077] It can be understood that in the embodiment of the present application, the augmented state space model can be linearized and discretized to obtain a simplified model, which is more suitable for real-time control applications, and a power tracking objective function is generated according to the optimization function and the simplified model.

[0078] Specifically, in the embodiment of the present application, the original refined space model (i.e., the multi-time scale state space model) can be appropriately approximated and simplified, and parts with large time scale differences or parts irrelevant to the control objective can be omitted to obtain a simplified prediction model for control.

[0079] The direct control variables for the phase modulation operation on the turbine side are the opening degrees of the throttle valve and the main turbine control valve, and the mass flow rate of the high-temperature heat-conducting oil at the inlet of the heat exchanger:

[0080]

[0081] The state variables are the mass flow rates of each turbine, the temperature difference on the air side of the heat exchanger, and the rotational speed of the turbine, as shown in the formula:

[0082]

[0083] Form an augmented state - space model by taking the thermal power required for the no - load losses of each - stage turbine - generator set as an auxiliary state variable:

[0084]

[0085] After linearizing and discretizing the above - mentioned model, a standard form convenient for MPC control is obtained, as shown in the following formula:

[0086]

[0087] Among them, H, J, and G are transformed constant matrices; is the augmented state - variable matrix; is the augmented state - variable matrix at time step k + 1; is the augmented state - variable matrix at time step k; k is the time step; is the control - variable matrix at time step k; is the turbine output power at time step k.

[0088] In the embodiment of the present application, the power - tracking objective function is:

[0089]

[0090] Among them, is the augmented state - variable matrix is the control - variable matrix; N is the number of turbine stages; is the thermal power required to overcome the no - load losses of the turbine - generator set; is the rated power of the turbine - generator set in no - load operation.

[0091] It should be noted that the key to the optimization objective of the phase - modulation operation on the turbine side is to adjust the opening degrees of the throttle valve and the main turbine - regulating valve in real - time to minimize the power deviation required to overcome the no - load losses, and at the same time minimize the total heat consumption during the phase - modulation stage, and possibly reduce the actions of the controller to extend the service life of the equipment. Therefore, the above - mentioned power - tracking objective function is constructed.

[0092] In step S104, deploy the power - tracking objective function in the MPC controller. During each sampling time of the MPC controller, use the power - tracking objective function to predict the operating parameters of the turbine side at the next moment, and realize the phase - modulation operation of the turbine side based on the predicted operating parameters.

[0093] It can be understood that the power tracking objective function can be deployed in the MPC controller in the embodiments of the present application. During each sampling time of the MPC controller, the power tracking objective function is used to predict the operating parameters on the turbine side at the next moment, and the phase modulation operation of the turbine side is realized based on the predicted operating parameters, so that the turbine generator set on the turbine side is in an ultra-low power consumption operating state during the phase modulation stage, enabling the turbine generator set of the compressed air energy storage power station to achieve long-term small-flow economic and stable phase modulation operation.

[0094] Specifically, considering the constraints of the control quantity and the state quantity, during each sampling time of the MPC controller, by predicting the output at the next moment and calculating the error from the reference value, it is used as the objective function to solve the quadratic programming problem with safe operation constraints. The obtained control quantity is used for prediction and calculation in the next time step, thereby realizing the optimization control of the ultra-low power consumption phase modulation operation of the turbine generator set.

[0095] In summary, the phase modulation operation control method for the turbine side of the compressed air energy storage power station in the embodiments of the present application can achieve ultra-low power consumption phase modulation operation, realize long-term small-flow economic and stable operation of the unit, and is of great significance for fully tapping the flexible operation potential of the compressed air energy storage power station to improve economy and promoting its large-scale application in the new power system.

[0096] The operation of the compressed air energy storage power station in the phase modulation operation mode is as Figure 2 shown. During phase modulation operation, the gas volume required to drive the synchronous rotation of the turbine generator set is supplied by the gas storage reservoir. The turbine generator set is of an integrated design, and no coupling is provided in the middle to avoid the impact of frequent start-stop of the turbine unit on its lifespan. The turbine generator is a self-excited generator based on thyristor phase control rectification, and the excitation control is realized by a classic AVR. The mass flow rate of phase modulation operation is jointly regulated by the throttle valve at the outlet of the gas storage reservoir and the turbine inlet regulating valve. The mass flow rate of the heat-carrying working medium of the heat exchanger is regulated by the circulating oil pump at the outlet of the high-temperature heat storage tank.

[0097] The phase modulation operation control method for the turbine side of the compressed air energy storage power station specifically includes:

[0098] 1. Establish a state space model for the turbine side of the energy storage power station.

[0099] The expansion ratio and isentropic efficiency of the turbine can be determined by its inlet air mass flow rate and inlet air temperature. The components related to air flow regulation mainly include the throttle valve and the main turbine regulating valve group. Therefore, the long-term small-flow stable operation of the turbine generator set can be realized by controlling the opening degrees of the throttle valve and the main turbine regulating valve group and the mass flow rate of the heat-carrying working medium of the heat exchanger. Based on the mass conservation, energy conservation, and angular momentum conservation combined with the component thermodynamic formula, a multi-time scale state space model for the turbine side is established with the inlet temperature of the turbine and the outlet mass flow rate as the state quantities and the valve opening degrees and the mass flow rate of the heat transfer oil as the control quantities.

[0100] 2. A heat supplement optimization control method during the phase - modulation operation stage on the turbine side of the energy storage power station.

[0101] The main purpose of heat supplement during the phase - modulation stage is to control the turbine exhaust temperature. The flow rate of the heat - storage working medium is controlled by a circulating oil pump. During the energy - release power - generation stage, to achieve the best heat - exchange effect, the heat - capacity flow rates of the cold and hot fluids are usually controlled to be equal. During the phase - modulation stage, the flow rate of the heat - conducting oil needs to be optimized to minimize heat consumption on the premise of ensuring the turbine exhaust temperature. Taking the minimum consumption of heat - conducting oil during the phase - modulation stage as the control target, a heat - supplement optimization control method for phase - modulation operation is proposed. At the same time, the circulating oil pump can be in an intermittent working state during phase - modulation operation to ensure sufficient heat exchange between oil and gas on the premise of a certain total heat supplement.

[0102] 3. Optimization control of phase - modulation operation on the turbine side based on MPC.

[0103] Based on the established state - space model of the turbine side of the energy storage power station, with the minimum deviation of the power required for the turbine unit's phase - modulation operation and the minimum consumption of heat - conducting oil as the control targets, and considering the constraints of the system's state variables and control variables, a model - predictive optimization control method for phase - modulation operation on the turbine side is established.

[0104] According to the phase - modulation operation control method of the turbine side of the compressed - air energy - storage power station proposed in the embodiments of the present application, a multi - time - scale state - space model of the turbine side of the compressed - air energy - storage power station can be established. Considering the coupling relationship between the heat supplement amount and the turbine exhaust temperature during the phase - modulation stage, the optimization function during the phase - modulation stage is determined according to the coupling relationship. On the premise of meeting the requirements of the turbine exhaust temperature, the use amount of heat - conducting oil is minimized as much as possible to reduce energy consumption. And the thermal power required for the no - load loss of each - stage turbine generator set is used as an auxiliary state variable and added to the multi - time - scale state - space model to form an augmented state - space model, which further improves the model's description ability and control accuracy. The power - tracking target function is generated through the optimization function and the augmented state - space model, and the generated power - tracking target function is deployed in the MPC controller. The operating parameters at the next moment are predicted at each sampling time, and phase - modulation operation is realized based on these predictions, so as to be able to make a rapid and accurate response in a complex dynamic environment. Furthermore, during the phase - modulation stage, the turbine - side generator set operates in an ultra - low - power consumption state, enabling the turbine generator set of the compressed - air energy - storage power station to achieve long - time and small - flow economic and stable phase - modulation operation, and fully exploiting the operation potential of the compressed - air energy - storage power station.

[0105] Secondly, the phase - modulation operation control device of the turbine side of the compressed - air energy - storage power station proposed in the embodiments of the present application is described with reference to the accompanying drawings.

[0106] Figure 3 It is a block - diagram schematic of the phase - modulation operation control device of the turbine side of the compressed - air energy - storage power station in the embodiments of the present application.

[0107] As Figure 3 shown, the phase modulation operation control device 10 on the turbine side of the compressed air energy storage power station includes: a building module 100, a determination module 200, a generation module 300, and a prediction module 400.

[0108] Among them, the building module 100 is used to build a multi-time scale state space model on the turbine side of the compressed air energy storage power station; the determination module 200 obtains the coupling relationship between the heat supply amount and the turbine exhaust temperature during the phase modulation stage, and determines the optimization function during the phase modulation stage according to the coupling relationship; the generation module 300 is used to increase the thermal power required for the no-load loss of each stage of the turbine generator set as an auxiliary state variable into the multi-time scale state space model to form an augmented state space model, and generates a power tracking objective function according to the optimization function and the augmented state space model; the prediction module 400 is used to deploy the power tracking objective function into the MPC controller, and during each MPC controller sampling time, use the power tracking objective function to predict the operating parameters of the turbine side at the next moment, and realize the phase modulation operation of the turbine side based on the predicted operating parameters.

[0109] In the embodiment of the present application, the building module 100 is further used for: obtaining the volumes of the primary heat exchanger and the air pipeline on the turbine side of the energy storage power station; reducing the volumes of the primary heat exchanger and the air pipeline to the volume link of the turbine cavity; taking the air mass flow rate at the outlet of the volume link as the state quantity, taking the inlet and outlet temperatures of the air side of the heat exchanger and the turbine speed as state variables, and taking the throttle valve and the opening degrees of the main turbine regulating valves and the mass flow rate of the high-temperature heat transfer oil in the heat exchanger as control quantities, and building a multi-time scale state space model considering gas volume inertia, heat transfer inertia of the heat exchanger, and shafting mechanical inertia.

[0110] In the embodiment of the present application, the multi-time scale state space model includes a multi-variable coupling differential equation set, a steady-state thermodynamic characteristic model of the turbine subsystem, and a throttle valve and main turbine regulating valve group model. Among them, the multi-variable coupling differential equation set is constructed based on the mass conservation of the turbine chamber and the energy conservation law of heat exchange in the heat exchanger.

[0111] In the embodiment of the present application, the determination module 200 is further used for: obtaining the relationship between the mass flow rate of the heat transfer oil and the turbine inlet temperature; calculating the total heat supply power of the heat transfer oil on the turbine side during the energy release stage; analyzing the coupling relationship between the heat supply amount and the turbine exhaust temperature on the turbine side during the phase modulation stage according to the relationship between the mass flow rate of the heat transfer oil and the turbine inlet temperature, and the total heat supply power of the heat transfer oil on the turbine side during the energy release stage.

[0112] In the embodiment of the present application, the optimization function is:

[0113]

[0114] Among them, is the mass flow rate of the heat transfer oil flowing through the i-th stage heat exchanger during the phase modulation stage; and are the temperatures of the high-pressure air entering and leaving the i-th stage heat exchanger, respectively; and are the temperatures of the heat transfer oil entering and leaving the i-th stage heat exchanger, respectively; N g is the number of heat exchanger stages; c p,a is the specific heat capacity of air; is the mass flow rate of the air flowing through the heat exchanger; c p,HTF is the specific heat capacity of the heat transfer oil; s.t is the constraint condition.

[0115] In the embodiment of the present application, the generation module 300 is further configured to: linearize and discretize the augmented state space model to obtain a simplified model; generate a power tracking objective function according to the optimization function and the simplified model.

[0116] In the embodiment of the present application, the simplified model is:

[0117]

[0118] where H, J, and G are the transformed constant matrices; is the augmented state variable matrix; is the augmented state variable matrix at time step k + 1; is the augmented state variable matrix at time step k; k is the time step; is the control variable matrix at time step k; is the turbine output power at time step k.

[0119] In the embodiment of the present application, the power tracking objective function is:

[0120]

[0121] where is the augmented state variable matrix is the control variable matrix; N is the number of turbine stages; is the thermal power required to overcome the no-load loss of the turbine generator set; the rated power of the turbine generator set operating under no-load; is the optimization function.

[0122] It should be noted that the foregoing explanation of the embodiment of the phase modulation operation control method for the turbine side of the compressed air energy storage power station is also applicable to the phase modulation operation control device for the turbine side of the compressed air energy storage power station in this embodiment, and will not be repeated here.

[0123] According to the phase modulation operation control device on the turbine side of a compressed air energy storage power station proposed in an embodiment of the present application, a multi-time scale state space model of the turbine side of the compressed air energy storage power station can be established. Considering the coupling relationship between the heat supplement amount and the turbine exhaust temperature during the phase modulation stage, the optimization function during the phase modulation stage is determined according to the coupling relationship. On the premise of meeting the requirements of the turbine exhaust temperature, the usage amount of heat-conducting oil is minimized as much as possible, and the energy consumption is reduced. Moreover, the thermal power required for the no-load loss of each stage of turbine generator sets is used as an auxiliary state variable and added to the multi-time scale state space model to form an augmented state space model, further improving the model's description ability and control accuracy. The power tracking objective function is generated through the optimization function and the augmented state space model, and the generated power tracking objective function is deployed in the MPC controller. The operating parameters at the next moment are predicted at each sampling time, and the phase modulation operation is realized based on these predictions, so as to be able to make a rapid and accurate response in a complex dynamic environment. Furthermore, during the phase modulation stage, the turbine side generator sets operate in an ultra-low power consumption state, enabling the turbine generator sets of the compressed air energy storage power station to achieve long-term and small-flow economic and stable phase modulation operation, and fully exploiting the operation potential of the compressed air energy storage power station.

[0124] Figure 4 The structural schematic diagram of the electronic device provided by the embodiment of the present application. The electronic device may include:

[0125] A memory 401, a processor 402, and a computer program stored on the memory 401 and executable on the processor 402.

[0126] When the processor 402 executes the program, it implements the phase modulation operation control method on the turbine side of the compressed air energy storage power station provided in the above embodiment.

[0127] Furthermore, the electronic device further includes:

[0128] A communication interface 403 for communication between the memory 401 and the processor 402.

[0129] The memory 401 is used to store a computer program executable on the processor 402.

[0130] The memory 401 may include a high-speed RAM memory, and may also include non-volatile memory, such as at least one disk memory.

[0131] If the memory 401, the processor 402, and the communication interface 403 are implemented independently, the communication interface 403, the memory 401, and the processor 402 can be interconnected via a bus and communicate with each other. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, an Extended Industry Standard Architecture (EISA) bus, or the like. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 4 only a thick line is used to represent it in Figure 4 , but it does not mean that there is only one bus or one type of bus.

[0132] Optionally, in a specific implementation, if the memory 401, the processor 402, and the communication interface 403 are integrated on a single chip, the memory 401, the processor 402, and the communication interface 403 can communicate with each other through an internal interface.

[0133] The processor 402 may be a Central Processing Unit (CPU), or an Application Specific Integrated Circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present application.

[0134] The embodiments of the present application further provide a computer-readable storage medium, on which a computer program or instruction is stored. When the computer program or instruction is executed by a processor, the phase modulation operation control method of the turbine side of the compressed air energy storage power station as described above is implemented.

[0135] The embodiments of the present application further provide a computer program product, including a computer program or instruction. When the computer program or instruction is executed, the phase modulation operation control method of the turbine side of the compressed air energy storage power station as described above is implemented.

[0136] In the description of this specification, the descriptions referring to terms such as "one embodiment", "some embodiments", "examples", "specific examples", or "some examples", etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of this application. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or N embodiments or examples in a suitable manner. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0137] In addition, the terms "first" and "second" are used only for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of these features. In the description of this application, the meaning of "N" is at least two, such as two, three, etc., unless otherwise specifically defined.

[0138] Any process or method description shown in the flowchart or described in other ways herein can be understood to represent a module, segment, or part of code including one or N executable instructions for implementing a customized logical function or process. And the scope of the preferred embodiments of this application includes additional implementations, where the functions can be executed in a manner that may not be shown or discussed in sequence, including in a substantially simultaneous manner according to the involved functions or in a reverse order, which should be understood by those skilled in the art to which the embodiments of this application belong.

[0139] It should be understood that each part of this application can be implemented by hardware, software, firmware, or a combination thereof. In the above embodiments, the N steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one or a combination of the following techniques well known in the art: discrete logic circuits having logic gate circuits for implementing logical functions on data signals, application specific integrated circuits having appropriate combinational logic gate circuits, programmable gate arrays, field programmable gate arrays, etc.

[0140] Those of ordinary skill in the art of this technology can understand that all or part of the steps carried by the method of implementing the above embodiments can be completed by instructing relevant hardware through a program, and the program can be stored in a computer-readable storage medium. When the program is executed, it includes one or a combination of the steps of the method embodiment.

Claims

1. A control method for the phase modulation operation of the turbine side of a compressed air energy storage power station, characterized in that, It includes the following steps: Establish a multi-time scale state space model for the turbine side of a compressed air energy storage power station; Obtain the coupling relationship between the heat supplement amount and the turbine exhaust temperature during the phase modulation stage on the turbine side, and determine the optimization function for the phase modulation stage according to the coupling relationship; Take the thermal power required for the no-load loss of each stage of the turbine generator set as an auxiliary state variable and add it to the multi-time scale state space model to form an augmented state space model, and generate a power tracking objective function according to the optimization function and the augmented state space model; Deploy the power tracking objective function in the MPC controller. During each sampling time of the MPC controller, use the power tracking objective function to predict the operating parameters of the turbine side at the next moment, and realize the phase modulation operation of the turbine side based on the predicted operating parameters.

2. The phase modulation operation control method for the turbine side of a compressed air energy storage power station according to claim 1, wherein The establishment of the multi-time scale state space model for the turbine side of a compressed air energy storage power station includes: Obtain the volumes of the primary heat exchanger and the air pipeline on the turbine side of the energy storage power station; Reduce the volumes of the primary heat exchanger and the air pipeline to the volume link of the turbine cavity; Taking the air mass flow rate at the outlet of the volume link as the state quantity, taking the inlet and outlet temperatures of the air side of the heat exchanger and the turbine speed as state variables, and taking the opening degrees of the throttle valve and the main turbine control valve and the mass flow rate of the high-temperature heat transfer oil in the heat exchanger as control quantities, establish a multi-time scale state space model considering gas volume inertia, heat transfer inertia of the heat exchanger, and shaft system mechanical inertia.

3. The phase modulation operation control method for the turbine side of a compressed air energy storage power station according to claim 2, wherein The multi-time scale state space model includes a multi-variable coupling differential equation set, a steady-state thermodynamic characteristic model of the turbine subsystem, and a throttle valve and main turbine control valve group model. Among them, the multi-variable coupling differential equation set is constructed based on the mass conservation of the turbine chamber and the energy conservation law of heat exchange in the heat exchanger.

4. The phase modulation operation control method for the turbine side of a compressed air energy storage power station according to claim 1, wherein The obtaining of the coupling relationship between the heat supplement amount and the turbine exhaust temperature during the phase modulation stage on the turbine side includes: Obtain the relationship between the mass flow rate of the heat transfer oil and the turbine inlet temperature; Calculate the total heat supplement power of the heat transfer oil on the turbine side during the energy release stage; Analyze the coupling relationship between the heat supplement amount and the turbine exhaust temperature during the phase modulation stage on the turbine side according to the relationship between the mass flow rate of the heat transfer oil and the turbine inlet temperature and the total heat supplement power of the heat transfer oil on the turbine side during the energy release stage.

5. The control method for the phase modulation operation of the turbine side of a compressed air energy storage power station according to claim 1, wherein The optimization function is: Among them, is the mass flow rate of the heat transfer oil flowing through the i-th stage heat exchanger during the phase modulation stage; and are the temperatures of the high-pressure air entering and leaving the i-th stage heat exchanger, respectively; and are the temperatures of the heat transfer oil entering and leaving the i-th stage heat exchanger, respectively; N g is the number of heat exchanger stages; c p,a is the specific heat capacity of air; is the mass flow rate of the air flowing through the heat exchanger; c p,HTF is the specific heat capacity of the heat transfer oil; s.t is the constraint condition.

6. The phase modulation operation control method for the turbine side of a compressed air energy storage power station according to claim 1, characterized in that, The generating of the power tracking objective function according to the optimization function and the augmented state space model further includes: Linearize and discretize the augmented state space model to obtain a simplified model; Generate the power tracking objective function according to the optimization function and the simplified model.

7. The phase modulation operation control method for the turbine side of a compressed air energy storage power station according to claim 6, wherein the simplified model is: Among them, H, J, and G are transformed constant matrices; is the augmented state variable matrix; is the augmented state variable matrix at time step k + 1; is the augmented state variable matrix at time step k; k is the time step; is the control variable matrix at time step k; is the turbine output power at time step k.

8. The control method for the phase modulation operation of the turbine side of a compressed air energy storage power station according to claim 1 or 6, characterized in that, The power tracking objective function is: Among them, is the augmented state variable matrix; is the control variable matrix; N is the number of turbine stages; is the thermal power required to overcome the no-load loss of the turbogenerator set; The rated power of the turbogenerator set under no-load operation; is the optimization function.

9. A phase modulation operation control device for the turbine side of a compressed air energy storage power station, characterized in that, It includes: A establishing module, used to establish a multi-time scale state space model for the turbine side of a compressed air energy storage power station; A determining module, which obtains the coupling relationship between the heat supplement amount and the turbine exhaust temperature during the phase modulation stage on the turbine side, and determines the optimization function for the phase modulation stage according to the coupling relationship; A generation module, configured to increase the thermal power required for the no-load loss of each stage of the turbine generator set as an auxiliary state variable to the multi-time scale state space model to form an augmented state space model, and generate a power tracking objective function according to the optimization function and the augmented state space model; A prediction module, configured to deploy the power tracking objective function in the MPC controller, and within each MPC controller sampling time, use the power tracking objective function to predict the operating parameters of the turbine side at the next moment, and realize the phase modulation operation of the turbine side based on the predicted operating parameters.

10. An electronic device, characterized in that, Comprising: A memory, a processor, and a computer program stored on the memory and executable on the processor, wherein the processor executes the program to implement the phase modulation operation control method for the turbine side of the compressed air energy storage power station according to any one of claims 1-8.

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