Optimal control method and system for gas power plant

Abstract

The embodiment of the present application provides a kind of gas power plant optimization control method and system, belong to gas power plant technical field.The method comprises: the real-time operating parameter of target gas power plant is collected, and unit heat balance calculation model is constructed based on the real-time operating parameter;The heat balance calculation model is corrected based on the pre-constructed combustion auxiliary component incorporation scheme contrast library, and combustion auxiliary component incorporation scheme is obtained;The combustion auxiliary component incorporation scheme is executed, and unit operation information in execution process is monitored;The combustion auxiliary component incorporation scheme is corrected in real time based on the unit operation information until the combustion auxiliary component incorporation is completed.The present application scheme reduces the energy consumption of unit in full working condition, improves the economy of unit operation.

Description

Technical Field

[0001] This invention relates to the field of gas-fired power plant technology, specifically to an optimized control method and an optimized control system for gas-fired power plants. Background Technology

[0002] It is estimated that blending approximately 80% hydrogen fuel into natural gas can reduce carbon dioxide emissions by more than 50%. Therefore, research and demonstration applications of low-carbon fuel blending technologies such as hydrogen blending have broad application prospects and urgent practical significance. With the accelerated construction of new power systems and the rapid increase in the installed capacity of new energy sources, the instability and volatility of the power grid have been greatly increased. There is an urgent need for large-scale, long-term energy storage methods like hydrogen to play a role in smoothing fluctuations and regulating peak and frequency.

[0003] Currently, in renewable energy hydrogen production via water electrolysis, oxygen is directly discharged after hydrogen production, resulting in ineffective utilization of the oxygen. The renewable energy hydrogen production + gas turbine blending technology only considers the coupling of the hydrogen fuel system, neglecting the coupling of the oxygen and air working fluid systems, significantly reducing the overall energy efficiency of both the hydrogen production and consumption systems. To address this issue, an optimized solution is needed that effectively utilizes the oxygen generated during renewable water electrolysis hydrogen production and improves the overall energy efficiency of gas-fired power plants. Summary of the Invention

[0004] The purpose of this invention is to provide an optimized control method and system for gas-fired power plants, so as to at least solve the problems of oxygen waste and low overall energy efficiency of existing water electrolysis hydrogen production.

[0005] To achieve the above objectives, a first aspect of the present invention provides an optimized control method for a gas-fired power plant. The method includes: collecting real-time operating parameters of a target gas-fired power plant and constructing a unit heat balance calculation model based on the real-time operating parameters; modifying the heat balance calculation model based on a pre-constructed combustion auxiliary component blending scheme comparison library to obtain a combustion auxiliary component blending scheme; executing the combustion auxiliary component blending scheme and monitoring unit operating information during the execution process; and modifying the combustion auxiliary component blending scheme in real time based on the unit operating information until the combustion auxiliary component blending is completed.

[0006] Optionally, the real-time operating parameters include: ambient temperature information and unit basic load information.

[0007] Optionally, the step of constructing the unit heat balance calculation model based on the real-time operating parameters includes: constructing a BASELOAD basic load model based on the real-time operating parameters; and simulating the unit output and efficiency parameters based on the BASELOAD basic load model.

[0008] Optionally, the combustion aid component incorporation schemes include: oxygen incorporation, hydrogen incorporation, and simultaneous oxygen and hydrogen incorporation.

[0009] Optionally, the method further includes: constructing a reference library of combustion auxiliary component blending schemes, including: performing gradient blending of combustion auxiliary components under a preset specific load rate, and collecting the unit's output and efficiency values ​​after each blending; constructing a correspondence between the amount of combustion auxiliary component blended and the output and efficiency values ​​at each blending, obtaining multiple sets of correspondences; and generating a reference library of combustion auxiliary component blending schemes based on the multiple sets of correspondences.

[0010] Optionally, the step of modifying the heat balance calculation model based on a pre-built reference library of combustion auxiliary component blending schemes to obtain a combustion auxiliary component blending scheme includes: determining the current output and efficiency value of the unit based on the heat balance calculation model; using the current output and efficiency value of the unit as an index, modifying the heat balance model in the reference library of combustion auxiliary component blending schemes to obtain a modified heat balance model; applying safety restrictions to the modified heat balance model based on the unit's designed combustion chamber pressure pulsation threshold to obtain a restricted heat balance model; and determining a combustion auxiliary component blending scheme based on the restricted heat balance model.

[0011] Optionally, the method further includes: determining the component blending method of the combustion auxiliary component blending scheme, including: determining the component storage information of the gas storage tank and the component output information of the current component generating device; and determining the component gas supply scheme based on the component storage information and the component output information.

[0012] Optionally, the execution of the combustion auxiliary component blending scheme and the monitoring of unit operating information during the execution process include: performing component blending based on a preset step, and performing the discharge of the gas component to be replaced corresponding to the original gas supply based on the preset step; during the component blending process, real-time monitoring of the unit's operating vibration value, nitrogen oxide emission value, unit output status, and efficiency; the real-time correction of the combustion auxiliary component blending scheme based on the unit operating information until the combustion auxiliary component blending is completed includes: judging the combustion chamber combustion pressure pulsation value based on the operating vibration value, if it is greater than the preset step, and then adjusting the combustion auxiliary component blending scheme in real time until the combustion auxiliary component blending is completed. If a warning threshold is set, the amount of component added is reduced based on the combustion auxiliary component blending scheme until the combustion pressure pulsation value in the combustion chamber is less than the preset warning threshold. It is then determined whether the nitrogen oxide emission value is greater than the preset emission threshold. If it is, a control command for the ammonia injection amount of the denitrification system is generated and merged into the combustion auxiliary component blending scheme. If the unit output and efficiency change abruptly due to a preset gradient, a new combustion auxiliary component blending scheme is generated based on the changed unit output and efficiency and a pre-constructed comparison library of combustion auxiliary component blending schemes.

[0013] A second aspect of the present invention provides an optimized control system for a gas-fired power plant. The system includes: a data acquisition unit for acquiring real-time operating parameters of a target gas-fired power plant and constructing a unit heat balance calculation model based on the real-time operating parameters; a scheme generation unit for modifying the heat balance calculation model based on a pre-built reference library of combustion auxiliary component blending schemes to obtain a combustion auxiliary component blending scheme; an execution unit for executing the combustion auxiliary component blending scheme and monitoring unit operating information during the execution process; and a correction unit for real-time correction of the combustion auxiliary component blending scheme based on the unit operating information until the combustion auxiliary component blending is completed.

[0014] On the other hand, the present invention provides a computer-readable storage medium storing instructions that, when executed on a computer, cause the computer to perform the above-described gas-fired power plant optimization control method.

[0015] Through the above technical solution, the invention connects and coordinates the gas turbine unit, water electrolysis system, fuel system, waste heat boiler denitrification system, and environmental emission monitoring system through a control system. By monitoring relevant boundary conditions and combining existing data such as fuel flow, combustion temperature, pollutant emissions, and unit vibration, the invention achieves coupled control of the unit's fuel blending system and the gas turbine unit's combustion system. Within a safe threshold, this increases the turbine inlet temperature of the unit, reduces the unit's energy consumption under all operating conditions, and improves the unit's operational economy.

[0016] Other features and advantages of the embodiments of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0017] The accompanying drawings are provided to further illustrate embodiments of the present invention and form part of the specification. They are used together with the following detailed description to explain the embodiments of the present invention, but do not constitute a limitation thereof. In the drawings:

[0018] Figure 1 This is a flowchart of the steps of an optimized control method for a gas-fired power plant provided in one embodiment of the present invention;

[0019] Figure 2 This is a flowchart illustrating the implementation of an optimized control method for a gas-fired power plant according to one embodiment of the present invention.

[0020] Figure 3 This is a schematic diagram illustrating the relationship between combustion temperature and load according to one embodiment of the present invention;

[0021] Figure 4 This is a curve showing the change in power plant efficiency with intake air temperature, provided by one embodiment of the present invention.

[0022] Figure 5 This is a system structure diagram of an optimized control system for a gas-fired power plant provided in one embodiment of the present invention. Detailed Implementation

[0023] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0024] It is estimated that blending approximately 80% hydrogen fuel into natural gas can reduce carbon dioxide emissions by more than 50%. Therefore, research and demonstration applications of low-carbon fuel blending technologies such as hydrogen blending have broad application prospects and urgent practical significance. With the accelerated construction of new power systems and the rapid increase in the installed capacity of new energy sources, the instability and volatility of the power grid have been greatly increased. There is an urgent need for large-scale, long-term energy storage methods like hydrogen to play a role in smoothing fluctuations and regulating peak and frequency.

[0025] Currently, in the field of hydrogen production via water electrolysis, oxygen is directly discharged after hydrogen production, resulting in ineffective utilization of the oxygen. The new energy hydrogen production + gas turbine blending technology only considers the coupling of the hydrogen fuel system, neglecting the coupling of the oxygen and air working fluid systems, significantly reducing the overall energy efficiency of both the hydrogen production and consumption systems.

[0026] To address this problem, the present invention proposes an optimized control method and system for gas-fired power plants. This invention connects and coordinates the gas turbine unit, water electrolysis system, fuel system, waste heat boiler denitrification system, and environmental emission monitoring system through a control system. By monitoring relevant boundary conditions and combining existing data such as fuel flow, combustion temperature, pollutant emissions, and unit vibration, the system achieves coupled control of the unit's fuel blending system and the gas turbine unit's combustion system. Within a safe threshold, this increases the turbine inlet temperature, reduces energy consumption under all operating conditions, and improves the unit's operational economy.

[0027] Figure 1 This is a flowchart of a gas-fired power plant optimization control method according to one embodiment of the present invention. Figure 1 As shown, an embodiment of the present invention provides an optimized control method for a gas-fired power plant, the method comprising:

[0028] Step S10: Collect the real-time operating parameters of the target gas-fired power plant and construct a unit heat balance calculation model based on the real-time operating parameters.

[0029] Specifically, the present invention addresses combined cycle units equipped with water electrolysis hydrogen production devices and fuel mixing and air mixing systems. It researches and develops a method for precise hydrogen and oxygen addition to help improve the power generation efficiency of combined cycle units. This method is designed to monitor the gas turbine and fuel / air boundary conditions, and through calculation and processing by a computational regulator, obtain the adjustable potential of the maximum combustion temperature and emission characteristics inside the gas turbine.

[0030] In this embodiment of the invention, within the safety margin range of the gas turbine, the temperature before the gas turbine is increased by adding hydrogen and oxygen, which in turn increases the nitrogen oxide level at the gas turbine outlet. However, by precisely injecting ammonia into the waste heat boiler SCR denitrification system, the concentration is precisely reduced to below the emission standard. By trying three methods of adding oxygen, adding hydrogen, and simultaneously adding oxygen and hydrogen, the efficiency improvement of the unit within the safety margin is compared and analyzed at different load stages.

[0031] Preferably, the real-time operating parameters include: ambient temperature information and unit basic load information.

[0032] Furthermore, the step of constructing the unit heat balance calculation model based on the real-time operating parameters includes: constructing a BASELOAD basic load model based on the real-time operating parameters; and simulating the unit output and efficiency parameters based on the BASELOAD basic load model.

[0033] Step S20: Based on the pre-built reference library of combustion auxiliary component incorporation schemes, the heat balance calculation model is modified to obtain the combustion auxiliary component incorporation scheme.

[0034] Specifically, the combustion auxiliary component incorporation schemes include: oxygen incorporation, hydrogen incorporation, and simultaneous oxygen and hydrogen incorporation. The method further includes: constructing a reference library of combustion auxiliary component incorporation schemes, including: performing gradient incorporation of combustion auxiliary components at a preset specific load rate, and collecting the unit's output and efficiency values ​​after each incorporation; constructing a correspondence between the amount of combustion auxiliary component incorporated and the output and efficiency values ​​for each incorporation, obtaining multiple sets of correspondences; and generating a reference library of combustion auxiliary component incorporation schemes based on these multiple sets of correspondences.

[0035] 1) Under a specific load rate, by using only air oxygenation, we will try to test the effect of different oxygenation flow rates on the unit's output and efficiency, and propose the efficiency correction value of oxygenation on the unit's control model under different load rates, and embed the correction value into the calculation regulator.

[0036] Example 1:

[0037] By performing thermal balance model calculations on a gas turbine unit, it can be seen that under constant load rate, by incorporating oxygen generated from water electrolysis into the air, and maintaining the same oxygen-fuel ratio, the efficiency of the unit will be greatly improved by adding a certain amount of oxygen. This is because it saves some of the nitrogen compression power and reduces the amount of flue gas, resulting in a significant increase in the turbine inlet temperature. Table 1 shows the effect of different amounts of oxygen on the unit efficiency, without considering unit safety and emissions.

[0038]

[0039]

[0040] Table 1. Effect of different amounts of oxygen added at an oxygen-fuel ratio of 2.67 in an 85MW system.

[0041] 2) At a specific load rate, by using fuel-only hydrogen addition, we will try to explore the impact of different hydrogen addition flow rates on the unit's output and efficiency, and propose the efficiency correction value of hydrogen addition on the unit's control model at different load rates, and embed the correction value into the calculation regulator.

[0042] Example 2:

[0043] Meanwhile, through thermal balance model calculations on a certain gas turbine unit, it was found that under constant load rate, by blending hydrogen generated from water electrolysis into natural gas, and maintaining the same oxygen-fuel ratio, a certain amount of hydrogen is added. This reduces air compression power due to the reduced air demand. Furthermore, the adiabatic combustion temperature of hydrogen is higher than that of natural gas, leading to a significant increase in turbine inlet temperature despite reduced flue gas volume, thus greatly improving unit efficiency. Table 2 shows the impact of different amounts of hydrogen blended into the fuel on unit efficiency, without considering unit safety and emissions.

[0044]

[0045]

[0046] Table 2. Effect of different amounts of hydrogen incorporated at an oxygen-fuel ratio of 2.67 in an 85MW environment.

[0047] 3) At a specific load rate, by adopting the method of simultaneous air oxygenation and fuel hydrogenation, we will try the effect of different oxygenation and hydrogenation flow rates on the unit's output and efficiency, propose hydrogenation / oxygenation addition efficiency correction values ​​for the unit's control model under different load rates, and embed the correction values ​​into the calculation regulator.

[0048] Example 3:

[0049] Meanwhile, through thermal balance model calculations on a certain gas turbine unit, it was found that under constant load rate, by mixing hydrogen generated from water electrolysis into natural gas and oxygen into air, and maintaining the same oxygen-fuel ratio, adding a certain amount of hydrogen and oxygen reduces the air compression power. Simultaneously, the adiabatic combustion temperature of hydrogen is higher than that of natural gas, leading to a significant increase in the turbine inlet temperature while reducing flue gas volume, thus greatly improving the unit's efficiency. Table 3 shows the impact of different amounts of hydrogen and oxygen added to the fuel on unit efficiency, without considering unit safety and emissions.

[0050]

[0051]

[0052] Table 3. Effect of different amounts of hydrogen / oxygen on 85MW at an oxygen-fuel ratio of 2.67.

[0053] In embodiments of the present invention, such as Figure 2 The control strategy of this method is as follows: First, based on the existing ambient temperature and unit base load conditions, a baseload model is established for the existing unit. This model can calculate accurate unit output and efficiency parameters. Then, based on the calculation data of gas-fired power plants with oxygen / hydrogen / simultaneous hydrogen and oxygen addition, the heat balance model is corrected according to the influence of hydrogen and oxygen addition on unit efficiency under the same load, as shown in Tables 1, 2, and 3. The main correction is to the oxygen-to-fuel ratio of the unit, currently calculated to be 2.67. In reality, the air-fuel ratio (oxygen-fuel ratio) affects the unit's safe vibration and efficiency. A higher air-fuel ratio results in a larger excess air coefficient. When the unit experiences excessive combustion chamber pressure pulsation alarms, it is necessary to reduce the hydrogen addition ratio and increase the air-fuel ratio (increasing the excess air coefficient) to lower the combustion chamber temperature, as shown in Table 4.

[0054] 1 2057.97 1.5 1520.668 1.6 1446.487 1.8 1318.781 1.9 1263.397 2 1212.688 2.1 1166.08 2.5 1011.966 2.67 958.656 3 870.036

[0055] Table 4 Combustion chamber outlet temperature under different excess air coefficients

[0056] Step S30: Execute the combustion auxiliary component incorporation scheme and monitor the unit operation information during the execution process.

[0057] Specifically, based on the heat balance calculation model, the current output and efficiency of the unit are determined; using the current output and efficiency as an index, the heat balance model is corrected in the combustion auxiliary component blending scheme comparison library to obtain a corrected heat balance model; based on the unit's designed combustion chamber pressure pulsation threshold, the corrected heat balance model is subjected to safety restriction processing to obtain a restricted heat balance model; and based on the restricted heat balance model, a combustion auxiliary component blending scheme is determined.

[0058] Preferably, the method further includes determining the component blending method of the combustion auxiliary component blending scheme, including: determining the component storage information of the gas storage tank and the component output information of the current component generating device; and determining the component gas supply scheme based on the component storage information and the component output information.

[0059] In this embodiment of the invention, because the hydrogen and oxygen production from water electrolysis in new energy sources has peak-valley cycles, and photovoltaic power generation is not available on cloudy or rainy days and at night, the new energy water electrolysis hydrogen and oxygen production system is equipped with oxygen storage tanks and hydrogen storage tanks. Based on the safe and environmentally friendly operation of the unit, oxygen is preferentially drawn from the oxygen tank and added to the air. When the turbine inlet temperature of a partially loaded unit is low, and oxygen addition alone cannot achieve the maximum increase in turbine inlet temperature, fuel hydrogen addition is initiated, drawing hydrogen from the hydrogen tank and adding it to the fuel.

[0060] Preferably, by comparing Tables 1, 2, and 3, it can be seen that adding the hydrogen and oxygen produced in real time by the water electrolysis hydrogen and oxygen production unit to the unit, without considering the impact on the unit's safety and environmental characteristics, the addition of oxygen significantly improves the unit's efficiency. For example, in operating condition 3 with oxygen and operating condition 3 with hydrogen, the corresponding oxygen to hydrogen mass ratio is 8.7, which is close to the mass ratio of 8 in water electrolysis hydrogen production. Adding the above oxygen and hydrogen to the unit results in an efficiency increase of 3.3 percentage points from oxygen and 1.7 percentage points from hydrogen. The efficiency improvement effect of oxygen is nearly twice that of hydrogen. Therefore, oxygen addition should be given priority during unit operation.

[0061] Step S40: Based on the unit operation information, the combustion auxiliary component blending scheme is modified in real time until the combustion auxiliary component blending is completed.

[0062] Specifically, the process involves incorporating components based on a preset step, and discharging the gas components to be replaced corresponding to the original gas supply based on the preset step. During component incorporation, the unit's operating vibration value, nitrogen oxide emission value, unit output, and efficiency are monitored in real time. The real-time correction of the combustion auxiliary component incorporation scheme based on the unit's operating information until incorporation is complete includes: determining the combustion chamber pressure pulsation value based on the operating vibration value; if it exceeds a preset warning threshold, reducing the component incorporation amount based on the combustion auxiliary component incorporation scheme until the combustion chamber pressure pulsation value is less than the preset warning threshold; determining whether the nitrogen oxide emission value exceeds a preset emission threshold; if it does, generating a denitrification system ammonia injection quantity control command and merging the denitrification system ammonia injection quantity control command into the combustion auxiliary component incorporation scheme; and regenerating the combustion auxiliary component incorporation scheme based on the changed unit output and efficiency and a pre-built combustion auxiliary component incorporation scheme comparison library.

[0063] In one possible implementation, hydrogen and oxygen are added gradually. The hydrogen mass flow rate is gradually increased by a single increment of 0.01 kg / s, while the natural gas consumption of the unit is gradually decreased by a single decrease of 0.02399 kg / s under the same lower heating value conditions. The oxygen mass flow rate is gradually increased by a single increment of 0.08 kg / s, while the air mass flow rate is gradually decreased by a single decrease of 0.3457 kg / s.

[0064] Preferably, during the gradual hydrogen and oxygen addition process, the unit's operating vibration, nitrogen oxide emissions, and unit output and efficiency are monitored in real time. If the unit experiences a combustion chamber pressure pulsation alarm, it indicates that the unit's safety boundary has been reached. In this case, the control model is corrected to reduce the amount of hydrogen and oxygen added. After the safety vibration alarm signal disappears, it is checked whether the unit's nitrogen oxide emissions exceed the standard without the SCR denitrification system in operation. If they do, the ammonia injection rate of the denitrification system is increased to ensure that the unit's nitrogen oxide emissions meet national and local pollutant emission standards. If nitrogen oxide emissions and ammonia slip do not exceed the standard, the unit's existing parameters are maintained for stable operation, and the amount of hydrogen and oxygen added at the existing load is maintained. If nitrogen oxide emissions do not exceed the standard but ammonia slip exceeds the standard, the control model of the calculated regulator is corrected to reduce the amount of hydrogen and oxygen added at the existing load.

[0065] Furthermore, when there are significant changes in external temperature or unit load rate, resulting in a significant decrease in unit operating efficiency (an absolute decrease of 0.1%), the control model of the computational regulator is corrected. The influence of external temperature and load rate on the turbine inlet temperature is incorporated into the control model, which then suggests adjustments to the hydrogen and oxygen supply at specific loads and ambient temperatures. Generally, under otherwise constant conditions, a decrease in unit load rate leads to a decrease in turbine inlet temperature and efficiency (the pattern is as follows). Figure 3 As shown), a decrease in atmospheric temperature leads to a decrease in turbine inlet temperature and a decrease in unit efficiency (the pattern is as follows). Figure 4 (As shown). When the external temperature or unit load rate does not change significantly, and the unit's operating efficiency does not decrease significantly (the absolute value of efficiency decreases by 0.1%), then the hydrogen and oxygen supply will continue to be maintained at that level.

[0066] Figure 5 This is a system structure diagram of a gas-fired power plant optimization control system provided in one embodiment of the present invention. Figure 5 As shown, an embodiment of the present invention provides an optimized control system for a gas-fired power plant, the system comprising:

[0067] The data acquisition unit is used to acquire real-time operating parameters of the target gas-fired power plant and construct a unit heat balance calculation model based on the real-time operating parameters.

[0068] Specifically, the present invention addresses combined cycle units equipped with water electrolysis hydrogen production devices and fuel mixing and air mixing systems. It researches and develops a method for precise hydrogen and oxygen addition to help improve the power generation efficiency of combined cycle units. This method is designed to monitor the gas turbine and fuel / air boundary conditions, and through calculation and processing by a computational regulator, obtain the adjustable potential of the maximum combustion temperature and emission characteristics inside the gas turbine.

[0069] In this embodiment of the invention, within the safety margin range of the gas turbine, the temperature before the gas turbine is increased by adding hydrogen and oxygen, which in turn increases the nitrogen oxide level at the gas turbine outlet. However, by precisely injecting ammonia into the waste heat boiler SCR denitrification system, the concentration is precisely reduced to below the emission standard. By trying three methods of adding oxygen, adding hydrogen, and simultaneously adding oxygen and hydrogen, the efficiency improvement of the unit within the safety margin is compared and analyzed at different load stages.

[0070] Preferably, the real-time operating parameters include: ambient temperature information and unit basic load information.

[0071] Furthermore, the step of constructing the unit heat balance calculation model based on the real-time operating parameters includes: constructing a BASELOAD basic load model based on the real-time operating parameters; and simulating the unit output and efficiency parameters based on the BASELOAD basic load model.

[0072] The scheme generation unit is used to modify the heat balance calculation model based on a pre-built reference library of combustion auxiliary component incorporation schemes to obtain combustion auxiliary component incorporation schemes.

[0073] Specifically, the combustion auxiliary component incorporation schemes include: oxygen incorporation, hydrogen incorporation, and simultaneous oxygen and hydrogen incorporation. The method further includes: constructing a reference library of combustion auxiliary component incorporation schemes, including: performing gradient incorporation of combustion auxiliary components at a preset specific load rate, and collecting the unit's output and efficiency values ​​after each incorporation; constructing a correspondence between the amount of combustion auxiliary component incorporated and the output and efficiency values ​​for each incorporation, obtaining multiple sets of correspondences; and generating a reference library of combustion auxiliary component incorporation schemes based on these multiple sets of correspondences.

[0074] The execution unit is used to execute the combustion auxiliary component incorporation scheme and monitor the unit operation information during the execution process.

[0075] Specifically, based on the heat balance calculation model, the current output and efficiency of the unit are determined; using the current output and efficiency as an index, the heat balance model is corrected in the combustion auxiliary component blending scheme comparison library to obtain a corrected heat balance model; based on the unit's designed combustion chamber pressure pulsation threshold, the corrected heat balance model is subjected to safety restriction processing to obtain a restricted heat balance model; and based on the restricted heat balance model, a combustion auxiliary component blending scheme is determined.

[0076] Preferably, the method further includes determining the component blending method of the combustion auxiliary component blending scheme, including: determining the component storage information of the gas storage tank and the component output information of the current component generating device; and determining the component gas supply scheme based on the component storage information and the component output information.

[0077] In this embodiment of the invention, because the hydrogen and oxygen production from water electrolysis in new energy sources has peak-valley cycles, and photovoltaic power generation is not available on cloudy or rainy days and at night, the new energy water electrolysis hydrogen and oxygen production system is equipped with oxygen storage tanks and hydrogen storage tanks. Based on the safe and environmentally friendly operation of the unit, oxygen is preferentially drawn from the oxygen tank and added to the air. When the turbine inlet temperature of a partially loaded unit is low, and oxygen addition alone cannot achieve the maximum increase in turbine inlet temperature, fuel hydrogen addition is initiated, drawing hydrogen from the hydrogen tank and adding it to the fuel.

[0078] Preferably, by comparing Tables 1, 2, and 3, it can be seen that adding the hydrogen and oxygen produced in real time by the water electrolysis hydrogen and oxygen production unit to the unit, without considering the impact on the unit's safety and environmental characteristics, the addition of oxygen significantly improves the unit's efficiency. For example, in operating condition 3 with oxygen and operating condition 3 with hydrogen, the corresponding oxygen to hydrogen mass ratio is 8.7, which is close to the mass ratio of 8 in water electrolysis hydrogen production. Adding the above oxygen and hydrogen to the unit results in an efficiency increase of 3.3 percentage points from oxygen and 1.7 percentage points from hydrogen. The efficiency improvement effect of oxygen is nearly twice that of hydrogen. Therefore, oxygen addition should be given priority during unit operation.

[0079] The correction unit is used to make real-time corrections to the combustion auxiliary component blending scheme based on the unit operation information until the combustion auxiliary component blending is completed.

[0080] Specifically, the process involves incorporating components based on a preset step, and discharging the gas components to be replaced corresponding to the original gas supply based on the preset step. During component incorporation, the unit's operating vibration value, nitrogen oxide emission value, unit output, and efficiency are monitored in real time. The real-time correction of the combustion auxiliary component incorporation scheme based on the unit's operating information until incorporation is complete includes: determining the combustion chamber pressure pulsation value based on the operating vibration value; if it exceeds a preset warning threshold, reducing the component incorporation amount based on the combustion auxiliary component incorporation scheme until the combustion chamber pressure pulsation value is less than the preset warning threshold; determining whether the nitrogen oxide emission value exceeds a preset emission threshold; if it does, generating a denitrification system ammonia injection quantity control command and merging the denitrification system ammonia injection quantity control command into the combustion auxiliary component incorporation scheme; and regenerating the combustion auxiliary component incorporation scheme based on the changed unit output and efficiency and a pre-built combustion auxiliary component incorporation scheme comparison library.

[0081] In one possible implementation, hydrogen and oxygen are added gradually. The hydrogen mass flow rate is gradually increased by a single increment of 0.01 kg / s, while the natural gas consumption of the unit is gradually decreased by a single decrease of 0.02399 kg / s under the same lower heating value conditions. The oxygen mass flow rate is gradually increased by a single increment of 0.08 kg / s, while the air mass flow rate is gradually decreased by a single decrease of 0.3457 kg / s.

[0082] Preferably, during the gradual hydrogen and oxygen addition process, the unit's operating vibration, nitrogen oxide emissions, and unit output and efficiency are monitored in real time. If the unit experiences a combustion chamber pressure pulsation alarm, it indicates that the unit's safety boundary has been reached. In this case, the control model is corrected to reduce the amount of hydrogen and oxygen added. After the safety vibration alarm signal disappears, it is checked whether the unit's nitrogen oxide emissions exceed the standard without the SCR denitrification system in operation. If they do, the ammonia injection rate of the denitrification system is increased to ensure that the unit's nitrogen oxide emissions meet national and local pollutant emission standards. If nitrogen oxide emissions and ammonia slip do not exceed the standard, the unit's existing parameters are maintained for stable operation, and the amount of hydrogen and oxygen added at the existing load is maintained. If nitrogen oxide emissions do not exceed the standard but ammonia slip exceeds the standard, the control model of the calculated regulator is corrected to reduce the amount of hydrogen and oxygen added at the existing load.

[0083] Furthermore, when there are significant changes in external temperature or unit load rate, resulting in a significant decrease in unit operating efficiency (an absolute decrease of 0.1%), the control model of the computational regulator is corrected. The influence of external temperature and load rate on the turbine inlet temperature is incorporated into the control model, which then suggests adjusting the hydrogen and oxygen supply rates under specific load and ambient temperature conditions. Generally, under constant conditions, a decrease in unit load rate leads to a decrease in turbine inlet temperature and efficiency, as does a decrease in ambient temperature. When there are no significant changes in external temperature or unit load rate, and the unit operating efficiency does not decrease significantly (an absolute decrease of 0.1%), the current hydrogen and oxygen supply rate is maintained.

[0084] The present invention also provides a computer-readable storage medium storing instructions that, when executed on a computer, cause the computer to perform the above-described gas-fired power plant optimization control method.

[0085] Those skilled in the art will understand that all or part of the steps in the methods of the above embodiments can be implemented by a program instructing related hardware. This program is stored in a storage medium and includes several instructions to cause a microcontroller, chip, or processor to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as a USB flash drive, a portable hard drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0086] The optional embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the embodiments of the present invention are not limited to the specific details described above. Within the scope of the technical concept of the embodiments of the present invention, various simple modifications can be made to the technical solutions of the embodiments of the present invention, and these simple modifications all fall within the protection scope of the embodiments of the present invention. It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the embodiments of the present invention will not further describe the various possible combinations.

[0087] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the embodiments of the present invention, they should also be regarded as the content disclosed by the embodiments of the present invention.

Claims

1. An optimized control method for a gas-fired power plant, characterized in that, The method includes: Collect real-time operating parameters of the target gas-fired power plant and construct a unit heat balance calculation model based on the real-time operating parameters; The heat balance calculation model was modified based on a pre-built reference library of combustion auxiliary component incorporation schemes to obtain combustion auxiliary component incorporation schemes; wherein, The combustion aid component incorporation schemes include: oxygen incorporation, hydrogen incorporation, and simultaneous oxygen and hydrogen incorporation. The process of constructing a reference library of combustion aid component incorporation schemes includes: Under a preset specific load rate, the gradient incorporation of combustion auxiliary components is performed, and the unit's output and efficiency values ​​are collected after each incorporation. The correspondence between the amount of combustion auxiliary components incorporated and the output and efficiency values ​​at each incorporation is constructed, and multiple sets of correspondences are obtained. A reference library of combustion auxiliary component incorporation schemes is generated based on the multiple sets of correspondences. The combustion auxiliary component incorporation scheme is executed, and the unit operation information is monitored during the execution process; The combustion auxiliary component blending scheme is modified in real time based on the unit operation information until the combustion auxiliary component blending is completed.

2. The method according to claim 1, characterized in that, The real-time operating parameters include: Ambient temperature information and unit basic load information.

3. The method according to claim 1, characterized in that, The process of constructing the unit heat balance calculation model based on the real-time operating parameters includes: Based on the aforementioned real-time operating parameters, a BASELOAD basic load model is constructed. Based on the BASELOAD basic load model, the unit output and efficiency parameters are simulated.

4. The method according to claim 1, characterized in that, The heat balance calculation model is modified based on a pre-built reference library of combustion auxiliary component incorporation schemes to obtain combustion auxiliary component incorporation schemes, including: The current power output and efficiency value of the unit are determined based on the heat balance calculation model. Using the current unit's output and efficiency value as the starting index, the heat balance model is corrected in the combustion auxiliary component blending scheme comparison library to obtain the corrected heat balance model. Based on the unit design combustion chamber pressure pulsation threshold, the modified heat balance model is subjected to safety limitation processing to obtain a limited heat balance model. The combustion auxiliary component incorporation scheme was determined based on the constrained thermal balance model.

5. The method according to claim 1, characterized in that, The method further includes: The component incorporation method for determining the combustion aid component incorporation scheme includes: Determine the component storage information of the gas storage tank and the component output information of the current component generation device; Based on the component reserve information and the component production information, a component gas supply plan is determined.

6. The method according to claim 1, characterized in that, The execution of the combustion auxiliary component incorporation scheme and the monitoring of unit operating information during the execution process include: The component is incorporated based on a preset step, and the gas component that is replaced corresponding to the original gas supply is discharged based on the preset step. During the component blending process, the unit's operating vibration value, nitrogen oxide emission value, unit output and efficiency are monitored in real time. The real-time modification of the combustion auxiliary component blending scheme based on the unit operating information until the combustion auxiliary component blending is completed includes: Based on the operating vibration value, the combustion pressure pulsation value of the combustion chamber is determined. If it is greater than the preset warning threshold, the amount of component added is reduced based on the combustion auxiliary component addition scheme until the combustion pressure pulsation value of the combustion chamber is less than the preset warning threshold. Determine whether the nitrogen oxide emission value is greater than the preset emission threshold. If it is, generate a control command for the ammonia injection volume of the denitrification system and merge the control command for the ammonia injection volume of the denitrification system into the combustion auxiliary component blending scheme. If the unit's output and efficiency change abruptly due to a preset gradient, a new combustion auxiliary component incorporation scheme will be generated based on the changed unit output and efficiency and a pre-built reference library of combustion auxiliary component incorporation schemes.

7. An optimized control system for a gas-fired power plant, characterized in that, The system is used to execute the gas-fired power plant optimization control method according to any one of claims 1-6, and the system comprises: The data acquisition unit is used to acquire real-time operating parameters of the target gas-fired power plant and construct a unit heat balance calculation model based on the real-time operating parameters. The scheme generation unit is used to modify the heat balance calculation model based on a pre-built reference library of combustion auxiliary component incorporation schemes to obtain combustion auxiliary component incorporation schemes. An execution unit is used to execute the combustion auxiliary component incorporation scheme and monitor the unit operation information during the execution process; The correction unit is used to make real-time corrections to the combustion auxiliary component blending scheme based on the unit operation information until the combustion auxiliary component blending is completed.

8. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores instructions that, when executed on a computer, cause the computer to perform the gas-fired power plant optimization control method as described in any one of claims 1-6.

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