A dry low nitrogen combustion chamber combustion adjustment method

Abstract

This invention discloses a combustion adjustment method for a dry low-NOx combustor, belonging to the field of gas turbine combustion control technology. By selecting a combustion mode, the activation state of the combustion zone is obtained; combustion data of the dry low-NOx combustor is monitored in real time, and the flame temperature percentage and vent percentage are calculated; the average flame temperature is set according to the combustion mode and flame temperature percentage; based on the target combustion mode, the venting level is set and combined with annular flame temperature control to determine the combustion adjustment point and update the combustion window boundary. This invention achieves a balance between low NOx emissions, high stability, and high efficiency through three core technologies: fine division of combustion modes, independent control of annular temperature, and standardized boundary detection. Compared with existing technologies, it has a high degree of automation and strong repeatability, providing a reliable low-NOx combustion solution for industrial gas turbines.

Description

Technical Field

[0001] This invention relates to the field of gas turbine combustion control technology, specifically a method for adjusting combustion in a dry, low-NOx combustion chamber. Background Technology

[0002] Dry-type low-NOx combustors are widely used in industrial gas turbine systems, such as power generation and propulsion, to reduce NOx emissions and meet increasingly stringent environmental regulations. However, existing technologies have significant shortcomings, leading to unstable combustion efficiency and imprecise emission control, especially in dynamic scenarios such as gas turbine start-up, transition, and full-load operation.

[0003] Traditional combustion adjustment methods lack systematic mode division and boundary definition, relying on empirical adjustments. The mode switching points and quantitative parameters are not precisely defined, leading to unstable combustion states under load changes, which can easily cause emission exceedances or flameout risks. Secondly, existing methods rely on the overall control of the average flame temperature, ignoring the independent adjustment of the annular flame temperature. Controlling only the average flame temperature can cause high-frequency dynamic pressure fluctuations, increasing the risk of acoustic oscillations. At the same time, in specific scenarios, such as when the high emission point airflow velocity is low, the probability of lean combustion and flameout increases; when the low emission point airflow velocity is high, local high temperatures can easily lead to NOx exceedances. Finally, when optimizing low-NOx combustion, existing technologies struggle to balance emission control and combustion stability, limiting the performance of dry low-NOx combustors in industrial applications.

[0004] Therefore, there is an urgent need for a more refined and automated combustion adjustment method to address the shortcomings of existing technologies. Summary of the Invention

[0005] The purpose of this invention is to provide a combustion adjustment method for a dry low-NOx combustion chamber to solve the problems mentioned in the background art.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0007] A method for adjusting combustion in a dry, low-NOx combustion chamber, comprising the following steps:

[0008] Select the combustion mode and obtain the activation status of the combustion zone;

[0009] Real-time monitoring of combustion data in the dry low-NOx combustion chamber to calculate flame temperature percentage and venting percentage;

[0010] Set the average flame temperature according to the combustion mode and flame temperature percentage;

[0011] Based on the target combustion mode, set the venting level and combine it with the ring flame temperature control to determine the combustion adjustment point and update the combustion window boundary.

[0012] As a preferred embodiment of the dry low-NOx combustion chamber combustion adjustment method of the present invention, the combustion mode has ten levels, including B-2 mode, B-1 mode, B mode, BC / 2 mode, BC mode, BC2A mode, AB mode, AB9C mode, AB12C mode and ABC mode, wherein each level of combustion mode corresponds to a combustion zone activation state.

[0013] As a preferred embodiment of the combustion adjustment method for a dry low-NOx combustion chamber according to the present invention, the specific implementation process of real-time monitoring of combustion data of the dry low-NOx combustion chamber and calculating flame temperature percentage and exhaust percentage includes:

[0014] Combustion data of the dry low-NOx combustion chamber is collected by multi-source sensors. The combustion data includes temperature data, load data, fuel data and air supply data, and the air supply data includes the amount of gas released.

[0015] Obtain the highest average flame temperature, lowest average flame temperature, and average flame temperature, and calculate the percentage of flame temperature used to reflect the flame temperature path. The calculation formula is as follows:

[0016]

[0017] Based on the actual and maximum permissible venting volumes in the combustion chamber, the venting percentage, which reflects the airflow state of the combustion chamber, is calculated using the following formula:

[0018]

[0019] As a preferred embodiment of the dry low-NOx combustion chamber combustion adjustment method of the present invention, the step of setting the average flame temperature according to the initial combustion mode and flame temperature percentage includes:

[0020] Based on the initial combustion mode and path template, the flame temperature path is determined, the flame temperature percentage of the combustion chamber is obtained, and the average flame temperature is set. The path template includes the mapping rules between the combustion mode and the flame temperature path.

[0021] As a preferred embodiment of the combustion adjustment method for a dry low-NOx combustion chamber according to the present invention, the determination criteria for the combustion adjustment point include:

[0022] Combustion adjustment points include low emission point, medium emission point, high emission point, mode downgrade point, and mode upgrade point;

[0023] When the exhaust percentage is 45% to 55%, the combustion adjustment point is determined to be the mid-exhaust point.

[0024] When the exhaust percentage is 85% to 95%, the combustion adjustment point is determined to be the high exhaust point.

[0025] When the exhaust percentage is 5% to 15%, the combustion adjustment point is determined to be the low exhaust point.

[0026] When the venting percentage is 100%, the flame temperature reaches the lower boundary, and the flame temperature percentage reaches 5%, the combustion adjustment point is determined to be the mode downgrade point, and the combustion mode is downgraded.

[0027] When the evacuation percentage is 0%, the flame temperature reaches the upper boundary, and the flame temperature percentage reaches 95%, the combustion adjustment point is determined to be the mode upgrade point, and the combustion mode is upgraded.

[0028] The condition for reaching the upper boundary is to trigger any of the following conditions: acoustic vibration exceeding the limit and nitrogen oxide emissions exceeding the standard;

[0029] The condition for reaching the lower boundary is triggering any of the following conditions: carbon monoxide or unburned hydrocarbon exceeding the limit and the action of the active flameout prevention mechanism logic.

[0030] As a preferred embodiment of the dry low-NOx combustion chamber combustion adjustment method of the present invention, the specific implementation process of the annular flame temperature control includes:

[0031] The ring flame temperature includes the A-ring flame temperature, the B-ring flame temperature, and the C-ring flame temperature;

[0032] In BC and BC / 2 modes, when pressure pulsation in the combustion chamber is detected to be greater than the pressure pulsation threshold, the C-ring flame temperature is reduced; when partial flameout occurs in the combustion chamber, the C-ring flame temperature is increased.

[0033] In AB mode, when a pressure pulsation is detected to be greater than the pressure pulsation threshold, the flame temperature of ring A is reduced; when a partial flameout occurs, the flame temperature of ring A is increased.

[0034] In ABC mode, when pressure pulsation in the combustion chamber is detected to be greater than the pressure pulsation threshold, the flame temperature of ring A or ring C is reduced; when partial flameout occurs in the combustion chamber, the flame temperature of ring A or ring C is increased.

[0035] The conditions for reducing the flame temperature of a specified ring include continuously reducing the amount of fuel in the specified ring and increasing the amount of venting; the conditions for increasing the flame temperature of a specified ring are to continuously increase the amount of fuel in the specified ring and reduce the amount of venting.

[0036] As a preferred embodiment of the dry low-NOx combustion chamber combustion adjustment method of the present invention, the specific implementation process of calibrating the combustion window boundary includes:

[0037] The combustion window boundaries include the highest average flame temperature, the lowest average flame temperature, the maximum venting rate, and the minimum venting rate of the combustion chamber;

[0038] Based on the target combustion mode, the flame temperature percentage of the gas turbine is obtained and the flame temperature percentage difference is kept less than the preset difference within a fixed step size, and the activation state of the combustion zone is determined.

[0039] Adjust the load in the combustion chamber to make the exhaust percentage reach the mid-exhaust point determination condition, and run stably for a specified time, or until the emissions are stable, to calibrate the mid-exhaust point;

[0040] The calibration process is as follows: increase the flame temperature of the specified ring by a fixed step size until the maximum calibration boundary is reached; decrease the flame temperature of the specified ring by a fixed step size until the minimum calibration boundary is reached; modify the fuel quantity of the specified ring according to the maximum and minimum calibration boundaries while keeping the total fuel quantity unchanged; verify whether nitrogen oxides are within the target limit; if not, adjust the overall flame temperature and / or fuel distribution ratio.

[0041] Make the emptying percentage reach the high emptying point judgment condition, and repeat the calibration process to calibrate the high emptying point;

[0042] Adjust the exhaust percentage to 0%, extract the current average flame temperature, reduce the load until the flame temperature percentage remains at 5%, and calibrate the mode degradation point;

[0043] Make the emptying percentage reach the low emptying point judgment condition, and repeat the calibration process to calibrate the low emptying point;

[0044] Adjust the exhaust percentage to 0%, extract the current average flame temperature, increase the load until the flame temperature percentage remains at 95%, and calibrate the mode upgrade point.

[0045] Based on the temperature and gas release rate at different combustion adjustment points, the highest average flame temperature, lowest average flame temperature, maximum gas release rate, and minimum gas release rate of the combustion chamber are obtained, and the combustion window boundary is updated.

[0046] As a preferred embodiment of the dry low-NOx combustion chamber combustion adjustment method of the present invention, maintaining the flame temperature percentage difference within a fixed step size less than a preset difference includes:

[0047] In a specified combustion mode, adjust the gas release rate of the corresponding ring flame so that the flame temperature percentage difference is less than the preset difference;

[0048] When the load increases and the fuel supply increases, the corresponding ring flame temperature increases, thus reducing the amount of venting.

[0049] Increase the amount of gas released when the load decreases and fuel consumption decreases.

[0050] Compared with existing technologies, the beneficial effects achieved by this invention are as follows: In the dry low-NOx combustor combustion adjustment method provided by this invention, the combustion zone activation state is obtained by selecting a combustion mode; the combustion data of the dry low-NOx combustor is monitored in real time to calculate the flame temperature percentage and venting percentage; the average flame temperature is set according to the combustion mode and flame temperature percentage; the venting level is set according to the target combustion mode and combined with annular flame temperature control to determine the combustion adjustment point and update the combustion window boundary; this invention achieves a balance between low NOx emissions, high stability, and high efficiency through three core technologies: fine division of combustion modes, independent control of annular temperature, and standardized boundary detection. Compared with existing technologies, it has a high degree of automation and strong repeatability, providing a reliable low-NOx combustion solution for industrial gas turbines. Attached Figure Description

[0051] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof.

[0052] Figure 1 This is a flowchart of a dry low-NOx combustion chamber combustion adjustment method according to the present invention;

[0053] Figure 2 This is a schematic diagram of the combustion adjustment process in Mode B of the dry low-NOx combustion chamber combustion adjustment method of the present invention;

[0054] Figure 3 This is a schematic diagram of the BC mode combustion adjustment process of a dry low-NOx combustion chamber combustion adjustment method according to the present invention;

[0055] Figure 4 This is a schematic diagram of the AB mode combustion adjustment process of a dry low-NOx combustion chamber combustion adjustment method according to the present invention;

[0056] Figure 5 This is a schematic diagram of the ABC mode combustion adjustment process of a dry low-NOx combustion chamber combustion adjustment method according to the present invention. Detailed Implementation

[0057] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0058] Please see Figure 1 In this first embodiment: a method for adjusting the combustion of a dry low-NOx combustion chamber is provided, the method comprising the following steps:

[0059] Select the combustion mode and obtain the activation status of the combustion zone;

[0060] Real-time monitoring of combustion data in the dry low-NOx combustion chamber to calculate flame temperature percentage and venting percentage;

[0061] Set the average flame temperature according to the combustion mode and flame temperature percentage;

[0062] Based on the target combustion mode, set the venting level and combine it with the ring flame temperature control to determine the combustion adjustment point and update the combustion window boundary.

[0063] Specifically, there are ten combustion modes, including B-2 mode, B-1 mode, B mode, BC / 2 mode, BC mode, BC2A mode, AB mode, AB9C mode, AB12C mode and ABC mode. Each combustion mode corresponds to a combustion zone activation state.

[0064] Based on the gas turbine load requirements and start-up characteristics, the dry-type low-NOx three-ring combustor has 10 combustion modes, with the activation state of the combustion zone precisely controlled by mode commands:

[0065] Table 1 Combustion Mode Classification

[0066]

[0067] The standard dry-type low-NOx combustor gas turbine start-up process goes through the following 6 combustion modes (the combustion adjustment method is explained below using these 6 modes as examples): B mode (start-up) → BC / 2 mode (5% load) → BC mode (5% to 25% load) → BC2A mode (25% to 35% load) → AB mode (25% to 35% load) → ABC mode (50% to 100% load).

[0068] The control boundary for each combustion mode is a parallelogram-like structure consisting of the highest average flame temperature, the lowest average flame temperature, the maximum gas release rate, and the minimum gas release rate in the combustion chamber.

[0069] Flame temperature percentage is defined as the percentage position of the actual average flame temperature within the range of the highest and lowest average flame temperatures, reflecting the flame temperature path:

[0070] Define the exhaust percentage as a control parameter characterizing the compressor's exhaust volume, reflecting the airflow state in the combustion chamber:

[0071] In a specific combustion mode, the flame temperature path is set to 50% (the exhaust gas is adjusted to keep the flame temperature percentage around 50%). As the load increases and fuel increases, the flame temperature increases. To maintain the original set temperature, the exhaust gas decreases. When the amount of air entering the combustion chamber reaches its maximum (the exhaust percentage reaches 0%), fuel continues to increase, and the flame temperature approaches the upper boundary of the highest average flame temperature, thus upgrading the mode. Similarly, as the load decreases and fuel decreases, the exhaust gas increases to maintain the original set temperature. When the amount of air entering the combustion chamber reaches its minimum (the exhaust percentage reaches 100%), fuel continues to decrease, and the flame temperature approaches the lower boundary of the lowest average flame temperature. The amount of fuel approaches the maximum fuel limit, thus downgrading the mode.

[0072] Specifically, the implementation process for real-time monitoring of combustion data in the dry low-NOx combustion chamber and calculating flame temperature percentage and venting percentage includes:

[0073] Combustion data of the dry low-NOx combustion chamber is collected by multi-source sensors. The combustion data includes temperature data, load data, fuel data and air supply data, and the air supply data includes the amount of gas released.

[0074] Obtain the highest average flame temperature, lowest average flame temperature, and average flame temperature, and calculate the percentage of flame temperature used to reflect the flame temperature path. The calculation formula is as follows:

[0075]

[0076] Based on the actual and maximum permissible venting volumes in the combustion chamber, the venting percentage, which reflects the airflow state of the combustion chamber, is calculated using the following formula:

[0077]

[0078] Specifically, setting the average flame temperature based on the initial combustion mode and flame temperature percentage includes:

[0079] Based on the initial combustion mode and path template, the flame temperature path is determined, the flame temperature percentage of the combustion chamber is obtained, and the average flame temperature is set. The path template includes the mapping rules between the combustion mode and the flame temperature path.

[0080] Specifically, the criteria for determining the combustion adjustment point include:

[0081] Combustion adjustment points include low emission point, medium emission point, high emission point, mode downgrade point, and mode upgrade point;

[0082] When the exhaust percentage is 45% to 55%, the combustion adjustment point is determined to be the mid-exhaust point, where the fuel-air mixture is most stable, and the temperature window needs to be strictly controlled.

[0083] When the exhaust percentage is 85% to 95%, the combustion adjustment point is determined to be the high exhaust point. The airflow velocity is low, and it is easy to lose flame due to lean combustion. It is necessary to increase the exhaust volume to maintain combustion.

[0084] When the exhaust percentage is 5% to 15%, the combustion adjustment point is determined to be the low exhaust point. The airflow speed is fast and the risk of flameout is low, but local high temperature (NOx exceeding the standard) must be prevented.

[0085] When the venting percentage is 100%, the flame temperature reaches the lower boundary, and the flame temperature percentage reaches 5%, the combustion adjustment point is determined to be the mode downgrade point, and the combustion mode is downgraded.

[0086] When the evacuation percentage is 0%, the flame temperature reaches the upper boundary, and the flame temperature percentage reaches 95%, the combustion adjustment point is determined to be the mode upgrade point, and the combustion mode is upgraded.

[0087] The condition for reaching the upper boundary is to trigger any of the following conditions: acoustic vibration exceeding the limit and nitrogen oxide emissions exceeding the standard;

[0088] The condition for reaching the lower boundary is triggering any of the following conditions: carbon monoxide or unburned hydrocarbon exceeding the limit and the action of the active flameout prevention mechanism logic.

[0089] Specifically, the implementation process of the ring flame temperature control includes:

[0090] If only the average flame temperature is controlled, it will cause potential high-frequency dynamic pressure fluctuations. In order to avoid dynamic pressure fluctuations, the ring flame temperature also needs to be controlled separately.

[0091] The ring flame temperature includes the A-ring flame temperature, the B-ring flame temperature, and the C-ring flame temperature;

[0092] In BC and BC / 2 modes, when pressure pulsation in the combustion chamber is detected to be greater than the pressure pulsation threshold, the C-ring flame temperature is reduced; when partial flameout occurs in the combustion chamber, the C-ring flame temperature is increased.

[0093] In AB mode, when a pressure pulsation is detected to be greater than the pressure pulsation threshold, the flame temperature of ring A is reduced; when a partial flameout occurs, the flame temperature of ring A is increased.

[0094] In ABC mode, when pressure pulsation in the combustion chamber is detected to be greater than the pressure pulsation threshold, the flame temperature of ring A or ring C is reduced; when partial flameout occurs in the combustion chamber, the flame temperature of ring A or ring C is increased.

[0095] The conditions for reducing the flame temperature of a specified ring include continuously reducing the amount of fuel in the specified ring and increasing the amount of venting; the conditions for increasing the flame temperature of a specified ring are to continuously increase the amount of fuel in the specified ring and reduce the amount of venting.

[0096] Increasing the amount of fuel in rings A and C will reduce the amount of fuel in ring B, thus maintaining the same total combustion temperature; rings A and C are determined by artificial adjustment, and ring B is the portion of the total fuel after removing rings A and C.

[0097] Specifically, the specific implementation process for calibrating the combustion window boundary includes:

[0098] The combustion window boundaries include the highest average flame temperature, the lowest average flame temperature, the maximum venting rate, and the minimum venting rate of the combustion chamber;

[0099] Based on the target combustion mode, the flame temperature percentage of the gas turbine is obtained and the flame temperature percentage difference is kept less than the preset difference within a fixed step size, and the activation state of the combustion zone is determined.

[0100] Adjust the load in the combustion chamber to make the exhaust percentage reach the mid-exhaust point determination condition, and run stably for a specified time, or until the emissions are stable, to calibrate the mid-exhaust point;

[0101] The calibration process is as follows: increase the flame temperature of the specified ring by a fixed step size until the maximum calibration boundary is reached; decrease the flame temperature of the specified ring by a fixed step size until the minimum calibration boundary is reached; modify the fuel quantity of the specified ring according to the maximum and minimum calibration boundaries while keeping the total fuel quantity unchanged; verify whether nitrogen oxides are within the target limit; if not, adjust the overall flame temperature and / or fuel distribution ratio.

[0102] Make the emptying percentage reach the high emptying point judgment condition, and repeat the calibration process to calibrate the high emptying point;

[0103] Adjust the exhaust percentage to 0%, extract the current average flame temperature, reduce the load until the flame temperature percentage remains at 5%, and calibrate the mode degradation point;

[0104] Make the emptying percentage reach the low emptying point judgment condition, and repeat the calibration process to calibrate the low emptying point;

[0105] Adjust the exhaust percentage to 0%, extract the current average flame temperature, increase the load until the flame temperature percentage remains at 95%, and calibrate the mode upgrade point.

[0106] Based on the temperature and gas release rate at different combustion adjustment points, the highest average flame temperature, lowest average flame temperature, maximum gas release rate, and minimum gas release rate of the combustion chamber are obtained, and the combustion window boundary is updated.

[0107] Specifically, maintaining the flame temperature percentage difference within a fixed step size less than a preset difference includes:

[0108] In a specified combustion mode, adjust the gas release rate of the corresponding ring flame so that the flame temperature percentage difference is less than the preset difference;

[0109] When the load increases and the fuel supply increases, the corresponding ring flame temperature increases, thus reducing the amount of venting.

[0110] Increase the amount of gas released when the load decreases and fuel consumption decreases.

[0111] Example 1

[0112] Mode B boundary detection (e.g.) Figure 2 (As shown)

[0113] 1.1. Increase the power turbine speed command to trigger the target combustion mode and adjust the average flame temperature so that the flame temperature percentage is maintained at around 50%, ensuring that the gas turbine operates stably in this mode;

[0114] 1.2. Mid-row point calibration

[0115] 1) Adjust the load to bring the evacuation percentage to the middle discharge point, and run stably for 5 minutes, or until the discharge is stable.

[0116] 2) Increase the average flame temperature in fixed increments until it reaches the maximum boundary, triggering any of the following conditions:

[0117] ① Acoustic oscillation exceeds limits;

[0118] ②NOx emissions exceeded standards;

[0119] 3) Reduce the average flame temperature in fixed steps until it reaches the minimum boundary, i.e., trigger any of the following conditions:

[0120] ① Exceeding limits for carbon monoxide (CO) or unburned hydrocarbons (UHC);

[0121] ② The action of the active anti-flare mechanism logic (ABAL).

[0122] 4) Verify that nitrogen oxides are within the target limits. If not, adjust the overall flame temperature and / or fuel distribution ratio, and repeat the above process.

[0123] 1.3 High Discharge Point Calibration: Adjust the load to the high discharge point and repeat step 1.2.

[0124] 1.4 Low discharge point calibration: Adjust the load to the low discharge point and repeat step 1.2.

[0125] 1.5 Mode Upgrade Point Calibration: Set the exhaust percentage to 0%, adjust the average flame temperature to keep the flame temperature percentage at around 50%, and increase the load until the flame temperature percentage is kept at around 95%.

[0126] 1.6 Modify the combustion window boundary based on the four operating conditions recorded in the above steps.

[0127] 1.7 Reduce the load to the initial state and verify the calibration results.

[0128] BC / 2 mode boundary detection

[0129] 2.1 Increase load command to trigger target combustion mode, adjust average flame temperature to keep flame temperature percentage at around 50%, and ensure stable operation of gas turbine in this mode;

[0130] 2.2 Mid-level point calibration

[0131] 1) Adjust the load to bring the evacuation percentage to the middle discharge point, and run stably for 5 minutes, or until the discharge is stable.

[0132] 2) Increase the flame temperature of ring C by a fixed step size until it reaches the maximum boundary;

[0133] 3) Reduce the C-ring flame temperature in fixed increments until the minimum boundary is reached;

[0134] 4) Verify that nitrogen oxides are within the target limits. If not, adjust the overall flame temperature and / or fuel distribution ratio, and repeat the above process.

[0135] 2.3 High Discharge Point Calibration: Adjust the load to the high discharge point and repeat step 2.2.

[0136] 2.4 Mode Degradation Point Calibration: Set the exhaust percentage to 0%, adjust the average flame temperature to keep the flame temperature percentage at around 50%, and reduce the load to keep the flame temperature percentage at around 5%.

[0137] 2.5 Low discharge point calibration: Adjust the load to the low discharge point and repeat step 2.2.

[0138] 2.6 Mode upgrade point calibration: Set the exhaust percentage to 0%, adjust the average flame temperature to keep the flame temperature percentage at around 50%, and increase the load to keep the flame temperature percentage at around 95%.

[0139] 2.7 Reduce the load to downgrade the mode to mode B.

[0140] 2.8 Modify the combustion window boundary based on the five operating conditions recorded in the above steps.

[0141] 2.9 Increase the load to upgrade the mode to BC / 2 mode and verify the calibration results.

[0142] Example 2

[0143] BC mode boundary detection (e.g.) Figure 3 (As shown)

[0144] 3.1 Increase load command to trigger target combustion mode, adjust average flame temperature to keep flame temperature percentage at around 50%, and ensure stable operation of gas turbine in this mode;

[0145] 3.2 Mid-range point calibration

[0146] 1) Adjust the load to bring the evacuation percentage to the middle discharge point, and run stably for 5 minutes, or until the discharge is stable.

[0147] 2) Increase the flame temperature of ring C by a fixed step size until it reaches the maximum boundary;

[0148] 3) Reduce the C-ring flame temperature in fixed increments until the minimum boundary is reached;

[0149] 4) Verify that nitrogen oxides are within the target limits. If not, adjust the overall flame temperature and / or fuel distribution ratio, and repeat the above process.

[0150] 3.3 High Discharge Point Calibration: Adjust the load to the high discharge point and repeat step 3.2.

[0151] 3.4 Mode Degradation Point Calibration: Set the exhaust percentage to 0%, adjust the average flame temperature to keep the flame temperature percentage at around 50%, and reduce the load to keep the flame temperature percentage at around 5%.

[0152] 3.5 Low discharge point calibration: Adjust the load to the low discharge point and repeat step 3.2.

[0153] 3.6 Mode upgrade point calibration: Set the exhaust percentage to 0%, adjust the average flame temperature to keep the flame temperature percentage at around 50%, and increase the load to keep the flame temperature percentage at around 95%.

[0154] 3.7 Reduce the load to downgrade the mode to BC / 2 mode.

[0155] 3.8 Modify the combustion window boundary based on the five operating conditions recorded in the above steps.

[0156] 3.9 Increase the load to upgrade the mode to BC mode and verify the calibration results.

[0157] BC2A mode boundary detection

[0158] 4.1 Increase load command to trigger target combustion mode, adjust average flame temperature to keep flame temperature percentage at around 50%, and ensure stable operation of gas turbine in this mode;

[0159] 4.2 Mid-range point calibration

[0160] 1) Adjust the load to bring the evacuation percentage to the middle discharge point, and run stably for 5 minutes, or until the discharge is stable.

[0161] 2) Increase the flame temperature of ring C in fixed increments until it reaches the maximum boundary:

[0162] 3) Reduce the flame temperature of ring C in fixed increments until the minimum boundary is reached:

[0163] 4) Modify the fuel quantity in ring C according to the calibration results in steps 2) and 3) while keeping the total fuel quantity unchanged.

[0164] 5) Increase the flame temperature of ring A by a fixed step size until the maximum boundary is reached:

[0165] 5) Reduce the flame temperature of ring A in fixed steps until the minimum boundary is reached:

[0166] 4) Verify that nitrogen oxides are within the target limits. If not, adjust the overall flame temperature and / or fuel distribution ratio, and repeat the above process.

[0167] 4.3 High Discharge Point Calibration: Adjust the load to the high discharge point and repeat step 4.2.

[0168] 4.4 Mode Degradation Point Calibration: Set the exhaust percentage to 0%, adjust the average flame temperature to keep the flame temperature percentage at around 50%, and reduce the load to keep the flame temperature percentage at around 5%.

[0169] 4.5 Low discharge point calibration: Adjust the load to the low discharge point and repeat step S6.2.

[0170] 4.6 Mode upgrade point calibration: Set the exhaust percentage to 0%, adjust the average flame temperature to keep the flame temperature percentage at around 50%, and increase the load to keep the flame temperature percentage at around 95%.

[0171] 4.7 Reduce the load to downgrade the mode to BC mode.

[0172] 4.8 Modify the combustion window boundary based on the five operating conditions recorded in the above steps.

[0173] 4.9 Increase the load to upgrade the mode to BC2A mode and verify the calibration results.

[0174] Example 3

[0175] AB mode boundary detection (e.g.) Figure 4 (As shown)

[0176] 5.1 Increase load command to trigger target combustion mode, adjust average flame temperature to keep flame temperature percentage at around 50%, and ensure stable operation of gas turbine in this mode;

[0177] 5.2 Point Calibration

[0178] 1) Adjust the load to bring the evacuation percentage to the middle discharge point, and run stably for 5 minutes, or until the discharge is stable.

[0179] 2) Increase the flame temperature of ring A in fixed increments until it reaches the maximum boundary;

[0180] 3) Reduce the flame temperature of ring A in fixed steps until the minimum boundary is reached;

[0181] 4) Verify that nitrogen oxides are within the target limits. If not, adjust the overall flame temperature and / or fuel distribution ratio, and repeat the above process.

[0182] 5.3 High Discharge Point Calibration: Adjust the load to the high discharge point and repeat step 5.2.

[0183] 5.4 Mode Degradation Point Calibration: Set the exhaust percentage to 0%, adjust the average flame temperature to keep the flame temperature percentage at around 50%, and reduce the load to keep the flame temperature percentage at around 5%.

[0184] 5.5 Low discharge point calibration: Adjust the load to the low discharge point and repeat step 5.2.

[0185] 5.6 Mode upgrade point calibration: Set the exhaust percentage to 0%, adjust the average flame temperature to keep the flame temperature percentage at around 50%, and increase the load until the flame temperature percentage is kept at around 95%.

[0186] 5.7 Reduce the load to downgrade the mode to BC2A mode.

[0187] 5.8 Modify the combustion window boundary based on the five operating conditions recorded in the above steps.

[0188] 5.9 Increase the load to upgrade the mode to AB mode and verify the calibration results.

[0189] ABC mode boundary detection (e.g.) Figure 5 )

[0190] 6.1 Increase load command to trigger target combustion mode, adjust average flame temperature to keep flame temperature percentage at around 50%, and ensure stable operation of gas turbine in this mode;

[0191] 6.2 Point Calibration

[0192] 1) Adjust the load to bring the evacuation percentage to the middle discharge point, and run stably for 5 minutes, or until the discharge is stable.

[0193] 2) Increase the flame temperature of ring C in fixed increments until it reaches the maximum boundary:

[0194] 3) Reduce the flame temperature of ring C in fixed increments until the minimum boundary is reached:

[0195] 4) Modify the fuel quantity in ring C according to the calibration results in steps 2) and 3) while keeping the total fuel quantity unchanged.

[0196] 5) Increase the flame temperature of ring A by a fixed step size until the maximum boundary is reached:

[0197] 5) Reduce the flame temperature of ring A in fixed steps until the minimum boundary is reached:

[0198] 4) Verify that nitrogen oxides are within the target limits. If not, adjust the overall flame temperature and / or fuel distribution ratio, and repeat the above process.

[0199] 6.3 High Discharge Point Calibration: Adjust the load to the high discharge point and repeat step 6.2.

[0200] 6.4 Mode Degradation Point Calibration: Set the exhaust percentage to 0%, adjust the average flame temperature to keep the flame temperature percentage at around 50%, and reduce the load to keep the flame temperature percentage at around 5%.

[0201] 6.5 Low discharge point calibration: Adjust the load to the low discharge point and repeat step 6.2.

[0202] 6.6 Reduce the load to downgrade the mode to AB mode.

[0203] 6.8 Modify the combustion window boundary based on the four operating conditions recorded in the above steps.

[0204] 6.9 Increase the load to upgrade the mode to ABC mode and verify the calibration results.

[0205] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0206] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. 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 method for adjusting combustion in a dry, low-NOx combustion chamber, characterized in that, The method includes the following steps: Select the combustion mode and obtain the activation status of the combustion zone; Real-time monitoring of combustion data in the dry low-NOx combustion chamber; calculation of flame temperature percentage and venting percentage; acquisition of the highest average flame temperature, lowest average flame temperature, and average flame temperature; calculation of the flame temperature percentage reflecting the flame temperature path; the calculation formula is as follows: ； Based on the actual and maximum permissible venting volumes in the combustion chamber, the venting percentage, which reflects the airflow state of the combustion chamber, is calculated using the following formula: ； Set the average flame temperature based on the initial combustion mode and flame temperature percentage; Based on the target combustion mode, set the venting level and combine it with the ring flame temperature control to determine the combustion adjustment point and update the combustion window boundary.

2. The combustion adjustment method for a dry low-NOx combustion chamber according to claim 1, characterized in that, There are ten combustion modes, including B-2 mode, B-1 mode, B mode, BC / 2 mode, BC mode, BC2A mode, AB mode, AB9C mode, AB12C mode and ABC mode. Each combustion mode corresponds to a combustion zone activation state.

3. The combustion adjustment method for a dry low-NOx combustion chamber according to claim 2, characterized in that, The specific implementation process for real-time monitoring of combustion data in the dry low-NOx combustion chamber and calculating flame temperature percentage and vent percentage includes: Combustion data of the dry low-NOx combustion chamber is collected by multi-source sensors. The combustion data includes temperature data, load data, fuel data, and air supply data, including the amount of air released.

4. The combustion adjustment method for a dry low-NOx combustion chamber according to claim 3, characterized in that, The step of setting the average flame temperature based on the initial combustion mode and flame temperature percentage includes: Based on the initial combustion mode and path template, the flame temperature path is determined, the flame temperature percentage of the combustion chamber is obtained, and the average flame temperature is set. The path template includes the mapping rules between the combustion mode and the flame temperature path.

5. The combustion adjustment method for a dry low-NOx combustion chamber according to claim 4, characterized in that, The criteria for determining the combustion adjustment point include: Combustion adjustment points include low emission point, medium emission point, high emission point, mode downgrade point, and mode upgrade point; When the exhaust percentage is 45%~55%, the combustion adjustment point is determined to be the mid-exhaust point; When the exhaust percentage is 85%~95%, the combustion adjustment point is determined to be the high exhaust point; When the exhaust percentage is 5%~15%, the combustion adjustment point is determined to be the low exhaust point; When the venting percentage is 100%, the flame temperature reaches the lower boundary, and the flame temperature percentage reaches 5%, the combustion adjustment point is determined to be the mode downgrade point, and the combustion mode is downgraded. When the evacuation percentage is 0%, the flame temperature reaches the upper boundary, and the flame temperature percentage reaches 95%, the combustion adjustment point is determined to be the mode upgrade point, and the combustion mode is upgraded. The condition for reaching the upper boundary is to trigger any of the following conditions: acoustic vibration exceeding the limit and nitrogen oxide emissions exceeding the standard; The condition for reaching the lower boundary is triggering any of the following conditions: carbon monoxide or unburned hydrocarbon exceeding the limit and the action of the active flameout prevention mechanism logic.

6. The combustion adjustment method for a dry low-NOx combustion chamber according to claim 5, characterized in that, The specific implementation process of the ring flame temperature control includes: The ring flame temperature includes the A-ring flame temperature, the B-ring flame temperature, and the C-ring flame temperature; In BC and BC / 2 modes, when pressure pulsation in the combustion chamber is detected to be greater than the pressure pulsation threshold, the C-ring flame temperature is reduced; when partial flameout occurs in the combustion chamber, the C-ring flame temperature is increased. In AB mode, when a pressure pulsation is detected to be greater than the pressure pulsation threshold, the flame temperature of ring A is reduced; when a partial flameout occurs, the flame temperature of ring A is increased. In ABC mode, when pressure pulsation in the combustion chamber is detected to be greater than the pressure pulsation threshold, the flame temperature of ring A or ring C is reduced; when partial flameout occurs in the combustion chamber, the flame temperature of ring A or ring C is increased. The conditions for reducing the flame temperature of a specified ring include continuously reducing the amount of fuel in the specified ring and increasing the amount of venting; the conditions for increasing the flame temperature of a specified ring are to continuously increase the amount of fuel in the specified ring and decrease the amount of venting.

7. The combustion adjustment method for a dry low-NOx combustion chamber according to claim 6, characterized in that, The specific implementation process of updating the combustion window boundary includes: The combustion window boundaries include the highest average flame temperature, the lowest average flame temperature, the maximum venting rate, and the minimum venting rate of the combustion chamber; Based on the target combustion mode, the flame temperature percentage of the gas turbine is obtained and the flame temperature percentage difference is kept less than the preset difference within a fixed step size, and the activation state of the combustion zone is determined. Adjust the load in the combustion chamber to make the exhaust percentage reach the mid-exhaust point determination condition, and run stably for a specified time, or until the emissions are stable, to calibrate the mid-exhaust point; The calibration process is as follows: increase the flame temperature of the specified ring by a fixed step size until the maximum calibration boundary is reached; decrease the flame temperature of the specified ring by a fixed step size until the minimum calibration boundary is reached; modify the fuel quantity of the specified ring according to the maximum and minimum calibration boundaries while keeping the total fuel quantity unchanged; verify whether nitrogen oxides are within the target limit; if not, adjust the overall flame temperature and / or fuel distribution ratio. Make the emptying percentage reach the high emptying point judgment condition, and repeat the calibration process to calibrate the high emptying point; Adjust the venting percentage to 0%, extract the current average flame temperature, reduce the load until the flame temperature percentage remains at 5%, and calibrate the mode degradation point; Make the emptying percentage reach the low emptying point judgment condition, and repeat the calibration process to calibrate the low emptying point; Adjust the evacuation percentage to 0%, extract the current average flame temperature, increase the load until the flame temperature percentage remains at 95%, and calibrate the mode upgrade point. Based on the temperature and gas release rate at different combustion adjustment points, the highest average flame temperature, lowest average flame temperature, maximum gas release rate, and minimum gas release rate of the combustion chamber are obtained, and the combustion window boundary is updated.

8. The combustion adjustment method for a dry low-NOx combustion chamber according to claim 7, characterized in that: Maintaining the flame temperature percentage difference within a fixed step size to be less than a preset difference includes: In a specified combustion mode, adjust the gas release rate of the corresponding ring flame so that the flame temperature percentage difference is less than the preset difference; When the load increases and the fuel supply increases, the corresponding ring flame temperature increases, thus reducing the amount of venting. Increase the amount of gas released when the load decreases and fuel consumption decreases.

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