Valve control methods and valve control systems for gas turbines

Abstract

This invention provides a valve control method for a gas turbine, comprising: acquiring basic measurement parameters related to the gas turbine at a target control time; calculating the calculated average flame temperature of the gas turbine combustion chamber corresponding to the target control time based on the basic measurement parameters; calculating the target temperature deviation corresponding to the target control time based on the calculated average flame temperature and a target flame temperature preset for the target operating state; and generating a control command for the compressor vent valve at the target control time based on the target temperature deviation. The valve control method for a gas turbine provided by this invention can adjust the opening of the compressor vent valve in real time based on the deviation between the calculated average flame temperature and the target flame temperature, thereby controlling the air-fuel ratio and ensuring that the gas turbine's pollutant emissions meet emission standards.

Description

Technical Field

[0001] This invention relates to the field of gas turbine control, and more specifically to a valve control method and valve control system for gas turbines. Background Technology

[0002] Aero engines and industrial gas turbines need to reduce nitrogen oxides (NOx). x The emissions of carbon monoxide (CO) and unburned hydrocarbons (UHC) must be reduced to meet emission standards. To ensure that gas turbine exhaust emissions meet standards, some power plants have to purchase flue gas desulfurization and denitrification devices, but the high maintenance costs have led gas turbine users to instead focus on reducing pollutant emissions at the source.

[0003] Low-emission gas turbines have improved combustion system design compared to conventional emission units. They control the combustion temperature in the combustion chamber through lean premixed combustion, thereby reducing NO emissions. x The content of [unspecified substance] is maintained at a low level. Low-emission gas turbines regulate the air flow from the compressor to the combustion chamber through the compressor vent valve to meet the air-fuel ratio adjustment requirements under different combustion modes and load conditions. Therefore, the control accuracy of the compressor vent valve plays a key role in the stable control of combustion temperature.

[0004] In realizing the concept of this invention, the inventors discovered at least the following problems in the related technology: the prior art usually adopts an open-loop control method, which controls the gas turbine to operate at a specified speed and pressure to control the vent valve. However, if the compressor vent of the low-emission gas turbine unit is controlled by an open-loop control, it will not be able to meet the unit's operational requirements and emission indicators for real-time adjustment of the fuel-air ratio under various combustion modes. Furthermore, due to the structural characteristics of the vent valve itself, when the actuator fails, the control system of the low-emission gas turbine unit cannot perform corresponding protective actions according to the safety protection level. Summary of the Invention

[0005] In view of this, the main objective of the present invention is to provide a valve control method and valve control system for gas turbines, in order to at least partially solve at least one of the aforementioned technical problems.

[0006] This invention provides a valve control method for a gas turbine, comprising:

[0007] Acquire basic measurement parameters related to the gas turbine at the target control time. These basic measurement parameters include: compressor inlet temperature, compressor inlet pressure, compressor outlet temperature, compressor outlet pressure, gas generator speed, fuel lower calorific value, total fuel demand, and combustion mode state parameters. The combustion mode state parameters correspond to the target operating state of the gas turbine at the target control time. The target operating state is one of the multiple operating states included in the entire operation of the gas turbine.

[0008] Based on the basic measurement parameters, the calculated average flame temperature of the gas turbine combustion chamber corresponding to the target control time is obtained;

[0009] Based on the calculated average flame temperature and the target flame temperature preset for the target operating state, the target temperature deviation corresponding to the target control time is calculated.

[0010] Based on the target temperature deviation, control commands are generated for the compressor vent valve at the target control time.

[0011] According to an embodiment of the present invention, generating a control command for the compressor vent valve at the target control time based on the target temperature deviation includes:

[0012] If the absolute value of the target temperature deviation is less than the first preset temperature deviation threshold, a first control command is generated to maintain the current valve opening of the compressor vent valve.

[0013] According to an embodiment of the present invention, generating a control command for the compressor vent valve at the target control time based on the target temperature deviation includes:

[0014] When the absolute value of the target temperature deviation is greater than the second preset temperature deviation threshold, the integral airflow fraction of the compressor vent valve corresponding to the target control time is calculated based on the target temperature deviation, wherein the second preset temperature deviation threshold is greater than the first preset temperature deviation threshold.

[0015] Based on the integral airflow fraction, a control command is generated for the compressor vent valve at the target control moment.

[0016] According to an embodiment of the present invention, generating a control command for the compressor vent valve at the target control moment based on the integral airflow fraction includes:

[0017] The integral airflow score is compared with the predetermined lower limit and upper limit of the integral;

[0018] When the integral gas flow fraction is greater than the predetermined lower limit of integral and less than the predetermined upper limit of integral, the target opening degree of the compressor vent valve corresponding to the target control time is calculated based on the integral gas flow fraction and the gas generator speed.

[0019] Based on the target opening degree, a second control command is generated for the compressor vent valve.

[0020] According to an embodiment of the present invention, generating a control command for the compressor vent valve at the target control moment based on the integral airflow fraction includes:

[0021] When the integral airflow fraction is greater than or equal to the predetermined integral upper limit, a third control command is generated so as to control the opening degree of the compressor vent valve to 100% and lock the compressor vent valve. When the target temperature deviation is less than the preset unlocking threshold, the locked state of the compressor vent valve is released.

[0022] When the integral airflow fraction is less than or equal to the predetermined integral lower limit, a fourth control command is generated to control the compressor vent valve opening to 0% and lock the compressor vent valve. When the target temperature deviation is greater than the preset unlocking threshold, the locked state of the compressor vent valve is released.

[0023] According to an embodiment of the present invention, the integral airflow fraction of the compressor vent valve corresponding to the target control time is calculated based on the target temperature deviation, including:

[0024] The target proportional coefficient is calculated based on the predetermined complex variable and the predetermined gain coefficient.

[0025] Based on the target temperature deviation and the target proportional coefficient, the compressor venting increment corresponding to the target control moment is calculated.

[0026] Calculate the integral value of the compressor venting volume increment over time based on the target control time, and obtain the integral airflow fraction of the compressor venting valve corresponding to the target control time.

[0027] According to an embodiment of the present invention, the calculation of the calculated average flame temperature of the gas turbine combustor corresponding to the target control time, based on basic measurement parameters, includes:

[0028] Based on the compressor inlet temperature, compressor inlet pressure, compressor outlet temperature, compressor outlet pressure, gas generator speed, fuel lower calorific value, total fuel demand, and combustion mode state parameters, intermediate measurement parameters are calculated. These intermediate measurement parameters include: compressor outlet enthalpy, fuel enthalpy, combustion chamber air-fuel ratio, estimated compressor inlet flow rate, air-fuel ratio based on calculated average flame temperature, and total combustion chamber pressure.

[0029] The calculated average flame temperature is obtained based on the lower heating value of the fuel, the enthalpy of the compressor outlet, the enthalpy of the fuel, the air-fuel ratio of the combustion chamber, the estimated value of the compressor inlet flow, the air-fuel ratio based on the calculated average flame temperature, and the total pressure of the combustion chamber.

[0030] According to an embodiment of the present invention, after generating the control command for the compressor vent valve at the target control time, the method further includes:

[0031] The actual opening degree of the compressor vent valve at the target control moment is obtained by a position sensor installed at the compressor vent valve.

[0032] Calculate the opening deviation between the actual opening degree and the target opening degree, where the target opening degree is the opening degree indicated by the control command;

[0033] Based on the target opening degree, the preset time coefficient, and the predetermined complex variables, the value representing the changing trend of the target opening degree in the time dimension is calculated.

[0034] Based on the opening deviation, gas generator speed, and trend characteristics, determine whether to issue a fault alarm for the compressor vent valve.

[0035] According to an embodiment of the present invention, determining whether to issue a fault alarm for the compressor vent valve based on the opening deviation, gas generator speed, and trend characteristic value includes:

[0036] If the opening deviation is greater than the preset opening deviation threshold, the gas generator speed is greater than the preset speed threshold, and the trend value is less than the preset value threshold, a fault alarm will be issued for the compressor vent valve.

[0037] Another aspect of the present invention provides a valve control system for a gas turbine, comprising:

[0038] The data transmission storage device is configured to store and / or transmit basic measurement parameters related to the gas turbine at the target control time. The basic measurement parameters include: compressor inlet temperature, compressor inlet pressure, compressor outlet temperature, compressor outlet pressure, gas generator speed, fuel lower calorific value, total fuel demand, and combustion mode state parameters. The combustion mode state parameters correspond to the target operating state of the gas turbine at the target control time. The target operating state is one of the multiple operating states included in the entire operation of the gas turbine.

[0039] The processor, which is communicatively connected to the data transfer storage device, is configured to perform the following operations:

[0040] Receive basic measurement parameters from the data transmission storage device;

[0041] Based on the basic measurement parameters, the calculated average flame temperature of the gas turbine combustion chamber corresponding to the target control time is obtained;

[0042] Based on the calculated average flame temperature and the target flame temperature preset for the target operating state, the target temperature deviation corresponding to the target control time is calculated.

[0043] Based on the target temperature deviation, generate control commands for the compressor vent valve at the target control time;

[0044] The actuator, which is connected in communication with the processor, is configured to receive control commands and perform driving actions on the compressor vent valve according to the control commands.

[0045] According to the valve control method and valve control system for gas turbines provided by the present invention, based on the calculated deviation between the average flame temperature and the target flame temperature, control commands can be generated for the compressor vent valve. This allows for real-time adjustment of the vent valve opening, thereby controlling the fuel-air ratio (the ratio of fuel to air) and ensuring that pollutant emissions meet emission standards. Therefore, the embodiments of the present invention at least partially solve the technical problems of the inability to adjust the fuel-air ratio in real time and the inability to achieve emission targets by controlling the vent valve. Attached Figure Description

[0046] Figure 1 A flowchart illustrating a valve control method for a gas turbine according to an embodiment of the present invention is shown schematically.

[0047] Figure 2 A control example of a valve control method for a gas turbine according to an embodiment of the present invention is shown;

[0048] Figure 3 This schematically illustrates a flowchart of generating control commands for the compressor vent valve at a target control moment based on the integral airflow fraction according to an embodiment of the present invention.

[0049] Figure 4 A flowchart illustrating a compressor vent valve control method according to an embodiment of the present invention is shown schematically.

[0050] Figure 5 A schematic diagram of a valve control system for a gas turbine according to an embodiment of the present invention is shown. Detailed Implementation

[0051] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0052] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the invention. In the following detailed description, numerous specific details are set forth to provide a thorough understanding of the embodiments of the invention for ease of explanation. However, it will be apparent that one or more embodiments may be practiced without these specific details. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0053] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. The terms “comprising,” “including,” etc., as used herein indicate the presence of features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0054] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein are to be interpreted in a manner consistent with the context of this specification, and not in an idealized or overly rigid way.

[0055] When using expressions such as "at least one of A, B, and C," the expression should generally be interpreted in accordance with the meaning commonly understood by a person skilled in the art (e.g., "a system having at least one of A, B, and C" should include, but is not limited to, systems having A alone, having B alone, having C alone, having A and B, having A and C, having B and C, and / or having A, B, and C, etc.). When using expressions such as "at least one of A, B, or C," the expression should generally be interpreted in accordance with the meaning commonly understood by a person skilled in the art (e.g., "a system having at least one of A, B, or C" should include, but is not limited to, systems having A alone, having B alone, having C alone, having A and B, having A and C, having B and C, and / or having A, B, and C, etc.).

[0056] This invention provides a valve control method and control system for gas turbines. In developing this invention, it was discovered that the air-fuel ratio (the ratio of fuel to air) affects the emissions of pollutants such as nitrogen oxides, carbon monoxide, and unburned hydrocarbons. Previous open-loop control methods for venting valves could not meet the real-time adjustment requirements of the air-fuel ratio under various combustion modes of the unit, nor could they achieve emission standards by controlling the venting valve. The valve control method for gas turbines provided by this invention can adjust the opening of the venting valve in real time based on the calculated deviation between the average flame temperature and the target flame temperature, thereby controlling the air-fuel ratio and achieving emission standards.

[0057] Figure 1 A flowchart illustrating a valve control method for a gas turbine according to an embodiment of the present invention is shown schematically.

[0058] like Figure 1 As shown, the valve control method for a gas turbine in this embodiment includes operations S101 to S104.

[0059] In operation S101, basic measurement parameters related to the gas turbine at the target control time are acquired. These basic measurement parameters include: compressor inlet temperature, compressor inlet pressure, compressor outlet temperature, compressor outlet pressure, gas generator speed, fuel lower calorific value, total fuel demand, and combustion mode status parameters. The combustion mode status parameters correspond to the target operating state of the gas turbine at the target control time. The target operating state is one of the multiple operating states included in the entire operation of the gas turbine.

[0060] In operation S102, the calculated average flame temperature of the gas turbine combustion chamber corresponding to the target control time is calculated based on the basic measurement parameters.

[0061] In operation S103, based on the calculated average flame temperature and the target flame temperature preset for the target operating state, the target temperature deviation corresponding to the target control time is calculated.

[0062] In operation S104, based on the target temperature deviation, a control command is generated for the compressor vent valve at the target control time.

[0063] According to an embodiment of the present invention, in operation S101, the target adjustment time can be the current time when the compressor vent valve opening needs to be adjusted.

[0064] According to embodiments of the present invention, combustion mode state parameters can be used to characterize the operating state of a gas turbine. A gas turbine can have multiple operating states throughout its operation, each operating state corresponding to a combustion mode, and each combustion mode corresponding to a combustion mode state parameter. The number of nozzles, combustion temperature within the combustion chamber, etc., differ under different combustion modes. The combustion mode state parameters for each combustion mode can be predetermined, and the parameter values ​​can be determined based on combustion test data.

[0065] According to an embodiment of the present invention, in operation S102, the calculated average flame temperature can be used to characterize the actual flame temperature of the gas turbine combustor at the target control moment.

[0066] According to an embodiment of the present invention, the target flame temperature can be preset during operation S103.

[0067] The operation of a gas turbine can have multiple operating states, and a corresponding target flame temperature can be set for each operating state. For example, the first operating state can correspond to the target flame temperature T1, and the second operating state can correspond to the target flame temperature T2.

[0068] The target flame temperature can be used to characterize the ideal value of the flame temperature under the corresponding operating conditions. When the flame temperature reaches the target flame temperature, the gas turbine can achieve the optimal operating conditions, such as achieving lower emissions of nitrogen oxides, carbon monoxide, and unburned hydrocarbons.

[0069] It should be noted that the target flame temperature is an ideal value. Since gas turbines typically cannot reach their optimal operating state during actual operation, the actual flame temperature may deviate from the target flame temperature; that is, the calculated average flame temperature may differ from the target flame temperature.

[0070] According to an embodiment of the present invention, in operation S104, the target temperature deviation can be used to characterize the deviation of the calculated average flame temperature from the target flame temperature. The target temperature deviation corresponding to the target control moment can be calculated, for example, by the following formula (1):

[0071] m = target flame temperature - calculated average flame temperature (1)

[0072] Where m can represent the target temperature deviation.

[0073] According to an embodiment of the present invention, the control command can be used to control the valve opening of the compressor vent valve. Generating the control command for the compressor vent valve at the target control moment can, for example, involve generating a corresponding control command based on the target temperature deviation, thereby minimizing the absolute value of the target temperature deviation, making the calculated average flame temperature closer to the target flame temperature, and thus bringing the gas turbine closer to its optimal operating state.

[0074] For example, the target temperature deviation at a certain moment is calculated, and a control command to "adjust the valve opening to 50%" is generated based on the target temperature deviation. Based on the control command, the valve opening of the compressor vent valve is adjusted to 50%, so that the calculated average temperature of the gas turbine is closer to the target flame temperature, thereby achieving the minimum emissions of nitrogen oxides, carbon monoxide and unburned hydrocarbons.

[0075] According to an embodiment of the present invention, since emissions of nitrogen oxides, carbon monoxide, and unburned hydrocarbons are lower at the target flame temperature, the above method calculates the average flame temperature and generates a control command for the compressor vent valve based on the target temperature deviation between the average flame temperature and the target flame temperature, controlling the vent valve to operate at the ideal opening degree. Furthermore, an ideal air-fuel ratio is obtained based on the ideal valve opening degree, so that under this air-fuel ratio condition, the flame temperature in the combustion chamber is adjusted towards the ideal target flame temperature, thereby achieving ideal emission levels for pollutants from the gas turbine. The above method achieves closed-loop control of the compressor vent valve based on real-time calculated flame temperature, ensuring the real-time adjustment of the air-fuel ratio according to the operating state of the low-emission unit, and reducing emissions of nitrogen oxides, carbon monoxide, and unburned hydrocarbons.

[0076] According to an embodiment of the present invention, specifically, generating a control command for the compressor vent valve at the target control time based on the target temperature deviation includes: generating a first control command for maintaining the current valve opening of the compressor vent valve when the absolute value of the target temperature deviation is less than a first preset temperature deviation threshold.

[0077] According to an embodiment of the present invention, when the absolute value of the target temperature deviation is less than a first preset temperature deviation threshold, the target temperature deviation can be recorded as 0.

[0078] According to an embodiment of the present invention, when the absolute value of the target temperature deviation is less than the first preset temperature deviation threshold, it indicates that the deviation between the calculated average temperature and the target flame temperature is small, and the actual operating state of the gas turbine is close to the optimal operating state. Therefore, there is no need to adjust the valve opening of the compressor vent valve.

[0079] For example: The current valve opening is 40%, the first preset temperature deviation threshold is set to 10, and the target temperature deviation at a certain moment is 5. Since the target temperature deviation is less than the first preset temperature deviation threshold, the target temperature deviation is recorded as 0, and a first control command is generated to maintain the current valve opening (40%).

[0080] According to an embodiment of the present invention, by comparing the absolute value of the target temperature deviation with a first preset temperature deviation threshold, it is possible to simply and accurately determine whether the valve opening needs to be adjusted.

[0081] According to an embodiment of the present invention, generating a control command for the compressor vent valve at the target control time based on the target temperature deviation may further include:

[0082] If the absolute value of the target temperature deviation is greater than the second preset temperature deviation threshold, the integral airflow fraction of the compressor vent valve corresponding to the target control time is calculated based on the target temperature deviation, wherein the second preset temperature deviation threshold is greater than the first preset temperature deviation threshold; based on the integral airflow fraction, a control command for the compressor vent valve at the target control time is generated.

[0083] According to an embodiment of the present invention, when the absolute value of the target temperature deviation is greater than the second preset temperature deviation threshold, it indicates that the deviation between the calculated average temperature and the target flame temperature is large, and the actual operating state of the gas turbine deviates significantly from the optimal operating state. Therefore, it is necessary to adjust the compressor venting volume to adjust the air-fuel ratio so that the actual operating state of the gas turbine is close to the optimal operating state.

[0084] According to an embodiment of the present invention, the compressor venting volume can be adjusted by adjusting the valve opening of the compressor venting valve.

[0085] For example, the current valve opening is 40%, the second preset temperature deviation threshold is set to 20, and the target temperature deviation at a certain moment is 25. Since the target temperature deviation is greater than the second preset temperature deviation threshold, it is necessary to adjust the valve opening of the compressor vent valve to regulate the compressor venting volume.

[0086] According to an embodiment of the present invention, the integral airflow fraction can be used to characterize the valve opening.

[0087] According to an embodiment of the present invention, specifically, the integral airflow fraction of the compressor vent valve corresponding to the target control time is calculated based on the target temperature deviation, including:

[0088] Operation 11: Calculate the target scaling factor based on the predetermined complex variable and the predetermined gain coefficient; where the predetermined complex variable is a necessary variable for time-domain and frequency-domain conversion.

[0089] Operation 12: Based on the target temperature deviation and the target proportional coefficient, calculate the compressor venting increment corresponding to the target control moment;

[0090] Operation 13: Calculate the integral value of the compressor venting volume increment over time based on the target control time, and obtain the integral airflow fraction of the compressor venting valve corresponding to the target control time.

[0091] According to an embodiment of the present invention, in operation 11, before calculating the target proportional coefficient, it is necessary to filter the target temperature deviation to remove abnormal data and improve the accuracy of the calculation.

[0092] According to an embodiment of the present invention, when the absolute value of the target temperature deviation is greater than a second preset temperature deviation threshold, it is necessary to adjust the compressor venting volume to bring the gas turbine's operating state closer to the ideal state. Furthermore, during the operation of the gas turbine, the target temperature deviation may differ at each operating moment, therefore, it is necessary to adjust the compressor venting volume in real time.

[0093] According to an embodiment of the present invention, the air-fuel ratio can be adjusted by adjusting the compressor venting volume, thereby adjusting the target temperature deviation.

[0094] For example, it could be: after 10 seconds of operation, the absolute value of the target temperature deviation 1 is greater than the second preset temperature deviation threshold, so the compressor venting volume needs to be adjusted to venting volume 1; after 11 seconds of operation, the absolute value of the target temperature deviation 2 is also greater than the second preset temperature deviation threshold, so the compressor venting volume needs to be further adjusted based on venting volume 1 to obtain venting volume 2; after 12 seconds of operation, the absolute value of the target temperature deviation 3 is also greater than the second preset temperature deviation threshold, so the compressor venting volume needs to be further adjusted based on venting volume 2 to obtain venting volume 3.

[0095] According to an embodiment of the present invention, in operation 12, the compressor venting increment can be used to characterize: the compressor venting amount that needs to be increased or decreased at the next target control moment compared with the compressor venting amount at the previous target control moment.

[0096] The compressor venting increment corresponding to the target control moment can be calculated using the following formula (2):

[0097] (2);

[0098] Where n is the incremental value of compressor venting volume; , is the predetermined gain coefficient, which can be obtained by calculating the converted speed of the gas generator; s is a predetermined complex variable.

[0099] According to an embodiment of the present invention, in operation 13, since it is necessary to calculate the compressor venting increment for the next target control time based on the compressor venting increment at the previous target control time, the venting increment can be continuously integrated to obtain the integral airflow fraction. Based on the integral airflow fraction, the compressor venting amount at the target control time can be determined, and the compressor venting amount can be adjusted by adjusting the valve opening.

[0100] For example, after 10 seconds of operation, the compressor discharge volume is discharge volume 1; after 11 seconds of operation, the compressor discharge volume increment 'a' is calculated; therefore, the compressor discharge volume at this time is discharge volume 1 + a, and the regulating valve opening is 40%; after 12 seconds of operation, the compressor discharge volume increment 'a' is integrated to obtain the integral airflow fraction, and based on the integral airflow fraction, the compressor discharge volume increment 'b' can be obtained; therefore, the compressor discharge volume at this time is discharge volume 1 + a + b, and the regulating valve opening is 60%; after 13 seconds of operation, the compressor discharge volume increment 'b' is integrated to obtain the compressor discharge volume increment 'c'; therefore, the compressor discharge volume at this time is discharge volume 1 + a + b + c, and the regulating valve opening is 90%.

[0101] According to an embodiment of the present invention, when the target temperature deviation is positive, the integral airflow fraction is positive, indicating that the valve opening needs to be increased; when the target temperature deviation is negative, the integral airflow fraction is negative, indicating that the valve opening needs to be decreased.

[0102] According to an embodiment of the present invention, in order to avoid infinite accumulation of integrals, a predetermined upper limit and a predetermined lower limit of integrals can be set: the maximum valve opening is 100% and the minimum is 0%; when the integral airflow fraction reaches the predetermined upper limit of integrals, it indicates that the valve opening has reached 100% and the valve opening can no longer be increased. At this time, integrals are stopped and the valve opening is locked at 100%; when the integral airflow fraction reaches the predetermined lower limit of integrals, it indicates that the valve opening has reached 0% and the compressor vent valve is completely closed. The valve opening can no longer be decreased. At this time, integrals are stopped and the valve opening is locked at 0%.

[0103] According to an embodiment of the present invention, the valve opening can be determined based on the integral airflow fraction. Setting a predetermined upper limit and a predetermined lower limit for integral can prevent the infinite accumulation of integrals and avoid invalid calculations.

[0104] According to an embodiment of the present invention, generating a control command for the compressor vent valve at the target control moment based on the integral airflow fraction includes:

[0105] Operation 21: Compare the integral airflow score with the predetermined integral lower limit and the predetermined integral upper limit;

[0106] Operation 22: When the integral gas flow fraction is greater than the predetermined lower limit of integral and less than the predetermined upper limit of integral, the target opening degree of the compressor vent valve corresponding to the target control time is calculated based on the integral gas flow fraction and the gas generator speed.

[0107] Operation 23: Generate a second control command for the compressor vent valve based on the target opening degree.

[0108] According to an embodiment of the present invention, in operation 22, when the integral airflow fraction is greater than the predetermined integral lower limit and less than the predetermined integral upper limit, it indicates that the valve opening is between 0% and 100%, and the valve opening is not in a locked state, so the valve opening can be adjusted.

[0109] According to an embodiment of the present invention, in operation 23, the second control command is used to control the compressor vent valve to reach the target opening degree.

[0110] For example, at the 5th second of operation, the integral airflow fraction 'a' is greater than the predetermined lower integral limit and less than the predetermined upper integral limit. The target opening at this moment is calculated to be 10%, and a second control command is generated to control the compressor vent valve opening to 10%. At the 6th second of operation, the integral airflow fraction 'b' is also greater than the predetermined lower integral limit and less than the predetermined upper integral limit. The target opening at this moment is calculated to be 50%, and a second control command is generated to control the compressor vent valve opening to 50%. At the 7th second of operation, the integral airflow fraction 'c' is also greater than the predetermined lower integral limit and less than the predetermined upper integral limit. The target opening at this moment is calculated to be 90%, and a second control command is generated to control the compressor vent valve opening to 90%.

[0111] According to an embodiment of the present invention, generating a control command for the compressor vent valve at the target control moment based on the integral airflow fraction includes:

[0112] When the integral airflow fraction is greater than or equal to the predetermined integral upper limit, a third control command is generated so as to control the opening degree of the compressor vent valve to 100% and lock the compressor vent valve. When the target temperature deviation is less than the preset unlocking threshold, the locked state of the compressor vent valve is released.

[0113] When the integral airflow fraction is less than or equal to the predetermined integral lower limit, a fourth control command is generated to control the compressor vent valve opening to 0% and lock the compressor vent valve. When the target temperature deviation is greater than the preset unlocking threshold, the locked state of the compressor vent valve is released.

[0114] According to an embodiment of the present invention, the third control command is used to lock the opening of the compressor vent valve at 100% and no longer adjust the opening of the compressor vent valve.

[0115] According to an embodiment of the present invention, a preset unlocking threshold can be set. When the target temperature deviation is less than the preset unlocking threshold, the locked state of the compressor vent valve is released, that is, the opening degree of the compressor vent valve can be adjusted.

[0116] For example: Set the preset unlock threshold to 0. During the 10-15 second run, if the integral airflow fraction is continuously greater than the preset integral upper limit, the valve opening will always be 100% during this period through the third control command; when the run is 16 seconds, if the target temperature deviation is less than the preset unlock threshold of 0, the compressor vent valve will be released from its locked state, and the opening of the compressor vent valve can be adjusted.

[0117] According to an embodiment of the present invention, the fourth control command is used to lock the opening of the compressor vent valve at 0%, and no longer adjust the opening of the compressor vent valve. When the target temperature deviation is greater than the preset unlocking threshold, the locked state of the compressor vent valve is released, and the opening of the compressor vent valve can be adjusted.

[0118] For example: Set the preset unlock threshold to 0. During the 17-20 second run, if the integral airflow fraction is continuously less than the preset integral lower limit, the valve opening will remain at 0% during this period via the fourth control command. When the run reaches 21 seconds, if the target temperature deviation is greater than the preset unlock threshold of 0, the compressor vent valve will be released from its locked state, and the opening of the compressor vent valve can be adjusted.

[0119] According to an embodiment of the present invention, the calculated average flame temperature of the gas turbine combustor corresponding to the target control time is obtained based on basic measurement parameters, including:

[0120] Based on the compressor inlet temperature, compressor inlet pressure, compressor outlet temperature, compressor outlet pressure, gas generator speed, fuel lower calorific value, total fuel demand, and combustion mode state parameters, intermediate measurement parameters are calculated. These intermediate measurement parameters include: compressor outlet enthalpy, fuel enthalpy, combustion chamber air-fuel ratio, estimated compressor inlet flow rate, air-fuel ratio based on calculated average flame temperature, and total combustion chamber pressure.

[0121] The calculated average flame temperature is obtained based on the lower heating value of the fuel, the enthalpy of the compressor outlet, the enthalpy of the fuel, the air-fuel ratio of the combustion chamber, the estimated value of the compressor inlet flow, the air-fuel ratio based on the calculated average flame temperature, and the total pressure of the combustion chamber.

[0122] According to an embodiment of the present invention, the intermediate measurement parameters can be calculated, for example, by the following formula (3):

[0123] (3);

[0124] in, It is a functional relationship. For compressor inlet temperature, For compressor inlet pressure, For compressor outlet temperature, Z represents the compressor outlet pressure, z represents the gas generator speed, b represents the lower calorific value of the fuel, w represents the total fuel demand, z represents the combustion mode state parameters, a represents the gas turbine compressor outlet enthalpy, c represents the fuel enthalpy, d represents the combustion chamber air-fuel ratio, and e represents the estimated compressor inlet flow rate.

[0125] According to an embodiment of the present invention, the calculated average flame temperature can be calculated, for example, by the following formula (4):

[0126] (4);

[0127] in, is the air-fuel ratio based on flame temperature, h is the total pressure in the combustion chamber, and k1, k2, k3, and k4 are constant coefficients.

[0128] Figure 2 A control example of a valve control method for a gas turbine according to an embodiment of the present invention is shown.

[0129] refer to Figure 2 For example: set the first preset temperature deviation threshold to 10, and the second preset temperature deviation threshold to 20.

[0130] During the 0-15 seconds of operation, because the target temperature deviation is continuously >0 and the absolute value of the deviation is continuously >20, the opening of the vent valve continues to increase until it reaches 100%, at which point the compressor vent valve is locked.

[0131] Starting from 15 seconds, the target temperature deviation begins to be less than 0, but the absolute value of the target temperature deviation is within 10, therefore the vent valve opening remains at 100%.

[0132] Starting from 18 seconds, if the target temperature deviation is continuously <-20, that is, if the absolute value of the target temperature deviation is continuously >20, the opening of the vent valve will gradually decrease until it reaches 0%, and then the compressor vent valve will be locked.

[0133] After about 35 seconds, the target temperature deviation is again greater than 0. Since the absolute value of the target temperature deviation is within 10, the opening of the compressor vent valve remains unchanged.

[0134] If the target temperature deviation is greater than 20°C after about 37 seconds, the valve opening of the compressor vent valve will be increased again.

[0135] After about 50 seconds, the target temperature deviation is again less than -20°C. The opening of the compressor vent valve gradually decreases and remains unchanged as the target temperature deviation stabilizes.

[0136] Figure 3 The flowchart illustrating the generation of control commands for the compressor vent valve at the target control moment based on the integral airflow fraction according to an embodiment of the present invention is shown.

[0137] like Figure 3 As shown, the method for generating control commands for the compressor vent valve at the target control time based on the integral airflow fraction in this embodiment includes operations S301 to S306.

[0138] In operation S301, the target temperature deviation is filtered.

[0139] In operation S302, the integral airflow fraction is obtained;

[0140] In operation S303, it is determined whether the integral airflow fraction is greater than the preset lower limit and less than the preset upper limit. When it is greater than the preset lower limit and less than the preset upper limit, a second control command is generated.

[0141] When operating S304, if the condition is not met (greater than the preset lower limit value and less than the preset upper limit value), the compressor vent valve is locked.

[0142] When operating S305, when the valve opening is 100%, it is determined whether the target temperature deviation is less than the preset unlocking threshold. If it is greater than the preset unlocking threshold, the compressor vent valve remains locked. When the target temperature deviation is less than the preset unlocking threshold, the locked state of the compressor vent valve is released.

[0143] When operating S306, if the valve opening is 0%, determine whether the target temperature deviation is greater than the preset unlocking threshold. If it is less than the preset unlocking threshold, continue to lock the compressor vent valve. If the target temperature deviation is greater than the preset unlocking threshold, release the locked state of the compressor vent valve.

[0144] According to an embodiment of the present invention, after generating the control command for the compressor vent valve at the target control time, the method further includes:

[0145] Operation 31: The actual opening degree of the compressor vent valve at the target control moment is collected by the position sensor set at the compressor vent valve.

[0146] Operation 32: Calculate the opening deviation between the actual opening and the target opening, where the target opening is the opening indicated by the control command;

[0147] Operation 33: Based on the target opening degree, the preset time coefficient, and the predetermined complex variable, calculate the value representing the trend of the target opening degree in the time dimension.

[0148] Operation 34: Based on the opening deviation, gas generator speed, and trend indicator value, determine whether to issue a fault alarm for the compressor vent valve.

[0149] According to an embodiment of the present invention, during operations 31 to 32, the control command for the compressor vent valve can characterize the target opening degree of the compressor vent valve. It should be noted that the target opening degree is an ideal value, and the actual opening degree during the operation of the gas turbine may deviate from the target opening degree.

[0150] According to an embodiment of the present invention, in operation 33, the trend characterization value can be calculated, for example, by the following formula (5):

[0151] (5)

[0152] in For preset time coefficient, The ideal target opening degree of the compressor vent valve is determined based on the temperature deviation between the calculated average flame temperature and the target flame temperature. The specific calculation method for the target opening degree value is the same as the specific calculation method in the aforementioned embodiments, and will not be repeated here.

[0153] According to an embodiment of the present invention, in operation 34, determining whether to issue a fault alarm for the compressor vent valve based on the opening deviation, gas generator speed, and trend characterization value includes:

[0154] If the opening deviation is greater than the preset opening deviation threshold, the gas generator speed is greater than the preset speed threshold, and the trend value is less than the preset value threshold, a fault alarm will be issued for the compressor vent valve.

[0155] According to an embodiment of the present invention, when a fault alarm is issued, the gas turbine control system issues an alarm and simultaneously prevents the gas turbine from starting normal operation mode.

[0156] According to an embodiment of the present invention, based on the opening deviation, gas generator speed, and trend characterization value, it can be determined whether to issue a fault alarm for the compressor vent valve, thereby enabling timely determination of whether the compressor vent valve has malfunctioned.

[0157] Figure 4 A flowchart illustrating a compressor vent valve control method according to an embodiment of the present invention is shown schematically.

[0158] like Figure 4 As shown, the compressor vent valve control method of this embodiment includes operations S401 to S406.

[0159] In operation S401, based on the calculated average flame temperature and the target flame temperature preset for the target operating state, the target temperature deviation corresponding to the target control time is calculated.

[0160] In operation S402, the target temperature deviation is filtered;

[0161] In operation S403, calculate the integral airflow fraction;

[0162] The S404 is operated to generate control commands;

[0163] When operating S405, the actual opening degree of the compressor vent valve is collected;

[0164] When operating S406, determine whether a fault alarm notification should be issued.

[0165] In another aspect of the invention, a valve control system for a gas turbine is also provided.

[0166] Figure 5 A schematic diagram of a valve control system for a gas turbine according to an embodiment of the present invention is shown.

[0167] like Figure 5 As shown, the valve control system 500 for a gas turbine according to an embodiment of the present invention includes:

[0168] The data transmission storage device 501 is configured to store and / or transmit basic measurement parameters related to the gas turbine at the target control time. These basic measurement parameters include: compressor inlet temperature, compressor inlet pressure, compressor outlet temperature, compressor outlet pressure, gas generator speed, fuel lower calorific value, total fuel demand, and combustion mode state parameters. The combustion mode state parameters correspond to the target operating state of the gas turbine at the target control time, and the target operating state is one of multiple operating states encompassed throughout the gas turbine's operation. The data transmission storage device 501 may include, for example, a data acquisition unit (e.g., acquiring compressor inlet temperature, compressor inlet pressure, compressor outlet temperature, compressor outlet pressure, gas generator speed, etc.), an input / output unit (e.g., for transmitting and issuing various types of data and control commands), and a data storage unit (e.g., for storing various types of data and commands).

[0169] The processor 502, communicatively connected to the data transmission storage device, is configured to perform the following operations: receive basic measurement parameters from the data transmission storage device; calculate the calculated average flame temperature of the gas turbine combustion chamber corresponding to the target control time based on the basic measurement parameters; calculate the target temperature deviation corresponding to the target control time based on the calculated average flame temperature and the target flame temperature preset for the target operating state; and generate a control command for the compressor vent valve at the target control time based on the target temperature deviation.

[0170] The actuator 503 is communicatively connected to the processor and is configured to receive control commands and execute driving actions on the compressor vent valve according to the control commands.

[0171] The position sensor 504, such as a linear displacement sensor, can be placed near the compressor vent valve to collect the actual opening degree of the compressor vent valve at the target control time and send the opening degree information back to the processor 502 so as to determine whether the compressor vent valve has malfunctioned and execute the corresponding protection action command.

[0172] The data transmission storage device 501 is connected to the processor 502, the processor 502 is connected to the actuator 503, and the processor 502 is connected to the position sensor 504 via network cables.

[0173] It should be understood that Figure 5 The number of data transmission storage device 501, processor 502, actuator 503, and position sensor 504 shown is merely illustrative. The number of these components can be adjusted according to implementation requirements.

[0174] The above specific embodiments further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A valve control method for a gas turbine, comprising: Acquire basic measurement parameters related to the gas turbine at the target control time. The basic measurement parameters include: compressor inlet temperature, compressor inlet pressure, compressor outlet temperature, compressor outlet pressure, gas generator speed, fuel lower calorific value, total fuel demand, and combustion mode state parameters. The combustion mode state parameters correspond to the target operating state of the gas turbine at the target control time. The target operating state is one of multiple operating states included in the entire operation of the gas turbine. Based on the aforementioned basic measurement parameters, the calculated average flame temperature of the gas turbine combustion chamber corresponding to the target control time is calculated. Based on the calculated average flame temperature and the target flame temperature preset for the target operating state, the target temperature deviation corresponding to the target control time is calculated. Based on the target temperature deviation, a control command is generated for the compressor vent valve at the target control time, including: If the absolute value of the target temperature deviation is less than a first preset temperature deviation threshold, a first control command is generated to maintain the current valve opening of the compressor vent valve. When the absolute value of the target temperature deviation is greater than the second preset temperature deviation threshold, the integral airflow fraction corresponding to the compressor vent valve at the target control time is calculated based on the target temperature deviation, wherein the second preset temperature deviation threshold is greater than the first preset temperature deviation threshold; based on the integral airflow fraction, a control command for the compressor vent valve at the target control time is generated; wherein the integral airflow fraction is used to characterize the valve opening of the compressor vent valve.

2. The method according to claim 1, wherein, Based on the integral airflow fraction, the control command generated for the compressor vent valve at the target control time includes: The integral airflow fraction is compared with a predetermined lower integral limit and a predetermined upper integral limit; When the integral airflow fraction is greater than a predetermined lower limit and less than a predetermined upper limit, the target opening degree of the compressor vent valve corresponding to the target control time is calculated based on the integral airflow fraction and the gas generator speed. Based on the target opening degree, a second control command is generated for the compressor vent valve.

3. The method according to claim 1, wherein, Based on the integral airflow fraction, the control command generated for the compressor vent valve at the target control time includes: When the integral airflow fraction is greater than or equal to a predetermined integral upper limit, a third control command is generated to control the opening degree of the compressor vent valve to 100% and lock the compressor vent valve. When the target temperature deviation is less than a preset unlocking threshold, the locked state of the compressor vent valve is released. When the integral airflow fraction is less than or equal to a predetermined integral lower limit, a fourth control command is generated to control the opening of the compressor vent valve to 0% and lock the compressor vent valve. When the target temperature deviation is greater than a preset unlocking threshold, the locked state of the compressor vent valve is released.

4. The method according to claim 1, wherein, The integral airflow fraction of the compressor vent valve corresponding to the target control moment, calculated based on the target temperature deviation, includes: The target proportional coefficient is calculated based on the predetermined complex variable and the predetermined gain coefficient. Based on the target temperature deviation and the target proportional coefficient, the compressor venting volume increment corresponding to the target control moment is calculated; Calculate the integral value of the compressor venting volume increment over time based on the target control time, and obtain the integral airflow fraction of the compressor venting valve corresponding to the target control time.

5. The method according to claim 1, wherein, Based on the aforementioned basic measurement parameters, the calculated average flame temperature of the gas turbine combustor corresponding to the target control moment is obtained, including: Intermediate measurement parameters are calculated based on compressor inlet temperature, compressor inlet pressure, compressor outlet temperature, compressor outlet pressure, gas generator speed, fuel lower calorific value, total fuel demand, and combustion mode state parameters. These intermediate measurement parameters include: compressor outlet enthalpy, fuel enthalpy, combustion chamber air-fuel ratio, estimated compressor inlet flow rate, air-fuel ratio based on calculated average flame temperature, and total combustion chamber pressure. The calculated average flame temperature is obtained based on the lower calorific value of the fuel, the enthalpy at the compressor outlet, the enthalpy of the fuel, the air-fuel ratio in the combustion chamber, the estimated compressor inlet flow rate, the air-fuel ratio based on the calculated average flame temperature, and the total pressure in the combustion chamber.

6. The method according to claim 1, further comprising, after generating the control command for the compressor vent valve at the target control moment: The actual opening degree of the compressor vent valve at the target control moment is obtained by a position sensor installed at the compressor vent valve. Calculate the opening deviation between the actual opening and the target opening, wherein the target opening is the opening indicated by the control command; Based on the target opening degree, the preset time coefficient, and the predetermined complex variable, the trend value of the target opening degree in the time dimension is calculated. Based on the opening deviation, gas generator speed, and the trend indicator value, determine whether to issue a fault alarm for the compressor vent valve.

7. The method according to claim 6, wherein, Based on the opening deviation, gas generator speed, and the trend indicator value, determining whether to issue a fault alarm for the compressor vent valve includes: If the opening deviation is greater than a preset opening deviation threshold, the gas generator speed is greater than a preset speed threshold, and the trend value is less than a preset value threshold, a fault alarm will be issued for the compressor vent valve.

8. A valve control system for a gas turbine, comprising: A data transmission storage device is configured to store and / or transmit basic measurement parameters related to the gas turbine at the target control time, wherein the basic measurement parameters include: compressor inlet temperature, compressor inlet pressure, compressor outlet temperature, compressor outlet pressure, gas generator speed, fuel lower calorific value, total fuel demand, and combustion mode state parameters, wherein the combustion mode state parameters correspond to the target operating state of the gas turbine at the target control time, and the target operating state is one of multiple operating states included in the entire operation of the gas turbine; The processor, communicatively connected to the data transmission storage device, is configured to perform the following operations: Receive the basic measurement parameters from the data transmission storage device; Based on the aforementioned basic measurement parameters, the calculated average flame temperature of the gas turbine combustion chamber corresponding to the target control time is calculated. Based on the calculated average flame temperature and the target flame temperature preset for the target operating state, the target temperature deviation corresponding to the target control time is calculated. Based on the target temperature deviation, a control command is generated for the compressor vent valve at the target control time, including: when the absolute value of the target temperature deviation is less than a first preset temperature deviation threshold, generating a first control command to maintain the current valve opening of the compressor vent valve; when the absolute value of the target temperature deviation is greater than a second preset temperature deviation threshold, calculating the integral airflow fraction corresponding to the compressor vent valve at the target control time based on the target temperature deviation, wherein the second preset temperature deviation threshold is greater than the first preset temperature deviation threshold; and generating a control command for the compressor vent valve at the target control time based on the integral airflow fraction; wherein the integral airflow fraction is used to characterize the valve opening of the compressor vent valve. An actuator, communicatively connected to the processor, is configured to receive the control commands and perform a driving action on the compressor vent valve according to the control commands.

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