Method, device and storage medium for non-steady-state regulation of automatic combustion of a gas turbine

Abstract

The application discloses a non-steady state regulation method and device for automatic combustion of a gas turbine and a storage medium, and comprises the following steps: when the working condition changes with time greater than the steady state allowable deviation, the steady state regulation is immediately switched to the non-steady state regulation; the non-steady state regulation comprises the following steps: when the adjusted object is always unchanged and different adjusted objects appear before and after, the pressure pulsation frequency band exceeds the standard, and the non-steady state combustion regulation is started; when the working condition changes with time is less than the steady state allowable deviation, after a certain time delay, if the change is less than the steady state allowable deviation during the time delay period, the steady state regulation is entered, the non-steady state regulation mode which is parallel to the steady state regulation and can be automatically switched is introduced, and the non-steady state bias value is not saved, so that the non-steady state process can be quickly responded, the interference on the subsequent working condition is avoided, the control target of instantaneous response and rapid subsidence in the variable working condition process is realized, and the regulation robustness in the multi-working condition continuous switching process is remarkably improved.

Description

Technical Field

[0001] This invention relates to the field of automatic combustion adjustment technology for gas turbines, specifically to unsteady-state adjustment methods, equipment, and storage media for automatic combustion in gas turbines. Background Technology

[0002] Gas turbine combustion systems experience rapid changes in operating conditions under non-steady-state conditions, such as variable loads and sudden temperature fluctuations. Existing automatic combustion adjustment systems for gas turbines employ a control strategy that operates under steady-state conditions—specifically, when the load is relatively stable and combustion parameter fluctuations are less than permissible deviations—resulting in a mechanism where combustion adjustment cannot intervene promptly when dangerous pressure pulsations suddenly appear or rapidly worsen during load changes. This makes it difficult to suppress the increase in pulsation amplitude, easily leading to combustion instability, increased thermoacoustic oscillations, and even triggering turbine trip protection in extreme cases, seriously threatening the unit's safety and availability. Furthermore, directly applying the control mechanism originally designed for steady-state conditions to non-steady-state conditions... In steady-state operating conditions, due to the constantly changing operating conditions, the bias value storage mechanism in the original adjustment logic may directly solidify the bias values ​​generated during the non-steady-state adjustment process into the incorrect operating conditions, ignoring the time-domain contradiction between the lag in fuel regulation effect and the rapid changes in operating conditions; the existing system has not established an operating condition identification mechanism and cannot automatically switch the adjustment mode according to the rate of change of operating conditions, resulting in untimely adjustment response or inappropriate adjustment strategies under non-steady-state operating conditions; the combustion chamber pressure pulsation includes multiple frequency bands, and different frequency bands correspond to different adjustment valves. The existing system has not established a priority-based dynamic scheduling mechanism and cannot make the optimal decision when multiple frequency bands exceed the limit at the same time. Summary of the Invention

[0003] The present invention proposes a non-steady-state regulation method, device, and storage medium for automatic combustion of gas turbines to solve the problems mentioned in the background art.

[0004] To achieve the above objectives, the present invention employs the following technical solution: The unsteady-state regulation method for automatic combustion of a gas turbine according to the present invention includes: When the operating conditions change over time and exceed the steady-state allowable deviation, the steady-state control immediately switches to unsteady-state control. Unsteady-state regulation includes: When the object being adjusted remains unchanged or different objects are introduced before and after, the pressure pulsation frequency exceeds the standard, and the non-steady-state fuel regulation is activated. When the operating condition changes less than the steady-state allowable deviation over time, after a certain time delay, if it remains less than the steady-state allowable deviation during the delay period, it will enter steady-state adjustment. The steady-state allowable deviation includes the load change rate threshold, the ambient temperature change rate threshold, the humidity change rate threshold, the air pressure change rate threshold, and the steady-state operating condition duration threshold.

[0005] Preferably, when the object being adjusted remains unchanged, if the pressure pulsation frequency exceeds the limit, the non-steady-state fuel adjustment is activated, including: After the first adjustment, wait for a certain period of time t before the adjusted object no longer exceeds the limit, and the non-steady bias value generated during the adjustment process slowly returns to 0; If the return point is reached during the return process, the return will stop. In the unsteady-state adjustment process of the automatic fuel adjustment system, when the controlled parameter A exceeds the limit, the system adjusts the valve to restore A to the normal range. After A no longer exceeds the limit and after a certain delay, the valve enters the return phase, attempting to return to the initial or reference position. To avoid the valve continuing to return to the limit, causing A to approach the fuel adjustment value again and triggering overshoot and fuel adjustment actions again, forming an infinite cycle of overshoot-adjustment-return-overshoot, the system presets a limit value lower than the fuel adjustment value as the return holding point. During the return process, if A touches the return holding point first, the valve immediately stops returning and maintains the current opening. Essentially, it sets a safety cutoff threshold on the return path, sacrificing part of the return stroke to exchange for system stability, so that the controlled variable remains in an acceptable range that, although not the target value, will not cause repeated oscillations.

[0006] If the level still exceeds the limit after a certain period of time following the initial adjustment, then proceed with the next step. If the target object exceeds the limit again during the return process, the return will be stopped and another step will be taken. The bias value is the cumulative value accumulated in real time for each adjustment step during the non-steady-state fuel adjustment process.

[0007] Preferably, when different controlled objects appear one after the other, if the pressure pulsation frequency exceeds the limit, the non-steady-state fuel regulation is activated, including: If, after one adjustment step, the pressure pulsation frequency band with the same valve, the same adjustment direction, and a higher adjustment priority exceeds the standard before the waiting time t has elapsed, then it is not necessary to wait for the time to end; adjustment should begin immediately for the pressure pulsation frequency band. If, after one adjustment, the pressure pulsation frequency band with the same valve, the same adjustment direction, and a lower adjustment priority exceeds the standard before the waiting time t has elapsed, then the adjustment for the pressure pulsation frequency band will be performed again after the waiting time has elapsed. If, after one adjustment step, the pressure pulsation frequency band with the same valve adjustment, opposite adjustment direction, and higher adjustment priority exceeds the standard before the waiting time t has elapsed, then the adjustment should not wait for the time to end, but should immediately begin to adjust the pressure pulsation frequency band. If, after one adjustment, the pressure pulsation frequency band exceeds the standard before the waiting time t has elapsed, even though the valve is adjusted in the same direction but with the opposite adjustment direction and a lower adjustment priority, then the adjustment for the pressure pulsation frequency band will be performed after the waiting time has elapsed.

[0008] Preferably, the step of immediately switching from steady-state regulation to non-steady-state regulation when the operating condition changes over time beyond the allowable steady-state deviation includes: The load change rate thresholds are as follows: If the load change rate is greater than 2% of the rated load per minute, and continues for 5 seconds, an unsteady-state switching will be immediately triggered. The threshold values ​​for the rate of change of ambient temperature are as follows: If the temperature change rate is greater than 2℃ / minute, switching will be triggered after 10 seconds. The humidity change rate thresholds are as follows: If the relative humidity change rate is greater than 3% / minute, switching will be triggered after 15 seconds. The threshold values ​​for the rate of change of air pressure are as follows: A pressure change rate greater than 0.3 kPa / min for 20 seconds triggers a switchover.

[0009] The duration thresholds for steady-state conditions are as follows: When all operating parameters change less than the steady-state allowable deviation and remain stable for more than 5 minutes, the system defaults to switching to steady-state mode; the adjustable range is 1 minute to 30 minutes, adaptable to different unit models.

[0010] Preferably, the unsteady bias value generated during the adjustment process slowly returns to 0, including: The return rate is as follows:

[0011]

[0012] in, Let be the valve bias value at time t. This is the initial bias value at the end of the unsteady-state adjustment. The exponential decay coefficient is... The linear backoff rate.

[0013] Preferably, the priority division is based on the following criteria: Emergency protection level: Pressure pulsation amplitude in any frequency band reaches 90% or more of the trip protection threshold, pulsation amplitude change rate is >50% per second, and pulsation in the low-frequency resonance band exceeds the standard, which can easily cause excessive vibration of the combustion chamber shell. High-risk suppression level: The amplitude of any frequency band pulse reaches 80% to 90% of the alarm threshold, the pulse in the medium frequency thermoacoustic oscillation frequency band exceeds the standard, which has caused the flue gas temperature dispersion to exceed the standard and triggered the alarm twice in the same frequency band within 1 minute. Medium-risk warning level: The pulsation amplitude in any frequency band reaches 30% to 60% of the warning threshold, the pulsation in the high-frequency ablation frequency band continues to exceed the standard, and the pulsation amplitude continues to rise during the load change process; Low-risk stable combustion level: The pulse amplitude in any frequency band reaches 30% to 60% of the warning threshold, the pulse fluctuates slightly without an upward trend, and the flame intensity fluctuates slightly under low load conditions; Optimized adjustment level: Pulsation amplitude is less than 30% of the warning threshold; The priority adjustment mechanism is as follows: For every 10% increase in the pulse amplitude of the same frequency band above the alarm threshold, the priority level increases by 1; for every 20% decrease in the alarm threshold, the priority level decreases by 1. If the pulse amplitude continues to rise for more than 3 seconds, the priority level is increased by 1 level; if it continues to fall for more than 5 seconds, the priority level is decreased by 1 level. Under non-steady-state conditions, the priority of all frequency bands is increased by 1 level by default; under emergency non-steady-state / start-stop / low load conditions, the priority is increased by 2 levels by default.

[0014] Preferably, pressure pulsation frequency band 2 is regulated by valve A, and pressure pulsation frequency band 4 is regulated by valve B. Currently, the operating condition is unsteady; if pressure pulsation frequency band 2 exceeds the limit, the unsteady fuel adjustment is activated. If, after adjusting pressure pulsation frequency band 2 to exceed the limit, the waiting time t has not elapsed, and pressure pulsation frequency band 4 adjusted by valve B exceeds the limit, valve A will remain stationary while valve B will immediately activate. If the limit is not exceeded after the preset waiting time, both valves will return to their original positions.

[0015] Preferably, when the operating condition changes less than the steady-state allowable deviation over time, after a certain time delay, if the change remains less than the steady-state allowable deviation for an extended period, then steady-state adjustment is initiated, including: After one adjustment, the unsteady-state regulation becomes steady-state regulation. After a certain period of time t, the object being adjusted no longer exceeds the limit, and the unsteady bias value generated during the unsteady-state regulation process slowly returns to 0. After one adjustment, the unsteady-state regulation becomes steady-state regulation. If the value still exceeds the limit after a certain period of time t, the steady-state regulation will be adjusted one step, and the unsteady-state bias value generated during the adjustment process will slowly return to 0. After one adjustment, the unsteady-state regulation becomes steady-state regulation. If the pressure pulsation frequency band with the same adjustment valve, the same adjustment direction, and a lower adjustment priority exceeds the standard before the waiting time t is reached, then after the waiting time ends, if the low-priority pressure pulsation frequency band still exceeds the standard, then steady-state adjustment is performed on the pressure pulsation frequency band. After that, the unsteady-state bias value generated during the unsteady-state regulation adjustment process slowly returns to 0. After one adjustment, the unsteady-state regulation becomes steady-state regulation. If the pressure pulsation frequency band with the same adjustment valve, opposite adjustment direction, and higher adjustment priority exceeds the standard before the waiting time t is reached, then it is not necessary to wait for the time to end. Steady-state adjustment is immediately started for the pressure pulsation frequency band. After that, the unsteady-state bias value generated during the unsteady-state regulation adjustment process slowly returns to 0. After one adjustment, the unsteady-state regulation becomes steady-state regulation. If the pressure pulsation frequency band with the same adjustment valve, opposite adjustment direction, and lower adjustment priority exceeds the standard before the waiting time t is reached, the adjustment for the pressure pulsation frequency band will be carried out after the waiting time ends. After that, the unsteady bias value generated during the unsteady-state regulation adjustment process will slowly return to 0. After one adjustment, the unsteady-state regulation becomes steady-state regulation. If the pressure pulsation frequency band regulated by valve B exceeds the limit before the waiting time t is reached, it is not necessary to wait for the time to end. Steady-state regulation is performed immediately. Valve A remains stationary, and valve B immediately moves. After the waiting time ends, the limit is not exceeded. Then, the unsteady-state bias value generated during the unsteady-state regulation process slowly returns to 0. After one adjustment, the unsteady-state regulation becomes steady-state regulation. After a waiting time t, it no longer exceeds the limit. During the slow return of the valve, it reaches the return holding point, and the unsteady-state bias value no longer returns to 0. After the waiting time ends, the unsteady-state bias value is stored as the steady-state bias value in the current bias value matrix.

[0016] In another aspect, the present invention also discloses a computer-readable storage medium storing a computer program, which, when executed by a processor, causes the processor to perform the steps of the method described above.

[0017] In another aspect, the present invention also discloses a computer device, including a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor performs the steps of the method described above.

[0018] As can be seen from the above technical solution, the present invention provides a non-steady-state regulation method for automatic combustion in gas turbines. Compared with the prior art, the present invention has the following advantages: 1. This invention solves the problem of insufficient regulation capability under non-steady-state conditions in existing technologies by introducing a non-steady-state regulation mode that runs parallel to steady-state regulation and can be automatically switched. Furthermore, the non-steady-state bias value is not stored, which can ensure rapid response in non-steady-state processes while avoiding interference with subsequent operating conditions. This achieves the control objective of instantaneous response and rapid decay during changing operating conditions, significantly improving the regulation robustness during continuous switching of multiple operating conditions.

[0019] 2. This invention monitors the rate of change of operating parameters in real time. When the rate of change exceeds the steady-state allowable deviation threshold, it immediately switches to the non-steady-state adjustment mode. When the rate of change is less than the threshold and continues for a certain delay, it switches to the steady-state adjustment mode. This enables automatic identification and switching of adjustment modes. It can intervene in a timely manner under operating conditions such as variable load and sudden temperature changes, thereby reducing the average peak pressure pulsation and the frequency of thermoacoustic oscillation events.

[0020] 3. This invention improves the regulation efficiency and decision-making rationality under multi-frequency band exceedance conditions through priority dynamic scheduling and multi-valve parallel adjustment, and reduces the number of unplanned shutdowns caused by combustion instability. Attached Figure Description

[0021] Figure 1 This is a schematic flowchart of the unsteady-state regulation method for automatic combustion of gas turbines according to the present invention.

[0022] Figure 2 This is a block diagram of the automatic switching threshold judgment logic for adjustment mode in this invention.

[0023] Figure 3 This is the logic diagram for multi-frequency band priority scheduling of the same valve in this invention. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, 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 some embodiments of the present invention, but not all embodiments.

[0025] like Figure 1 As shown, the unsteady-state regulation method for automatic combustion of a gas turbine in this embodiment includes: When the operating conditions change over time and exceed the steady-state allowable deviation, the steady-state control immediately switches to unsteady-state control. Unsteady-state regulation includes: When the object being adjusted remains unchanged or different objects are introduced before and after, the pressure pulsation frequency exceeds the standard, and the non-steady-state fuel regulation is activated. When the operating condition changes less than the steady-state allowable deviation over time, after a certain time delay, if it remains less than the steady-state allowable deviation during the delay period, it will enter steady-state adjustment. Steady-state allowable deviations include the load change rate threshold, the ambient temperature change rate threshold, the humidity change rate threshold, and the steady-state operating condition duration threshold.

[0026] When the object being adjusted remains unchanged, if the pressure pulsation frequency exceeds the limit, non-steady-state fuel regulation will be activated, including: After the first adjustment, wait for a certain period of time t before the adjusted object no longer exceeds the limit, and the non-steady bias value generated during the adjustment process slowly returns to 0; If the return point is reached during the return process, the return will stop. If the level still exceeds the limit after a certain period of time following the initial adjustment, then proceed with the next step. If the target object exceeds the limit again during the return process, the return will be stopped and another step will be taken.

[0027] like Figure 2As shown, the threshold for the rate of change of ambient temperature is as follows: If the temperature change rate is greater than 2℃ / minute, switching will be triggered after 10 seconds. The humidity change rate thresholds are as follows: If the relative humidity change rate is greater than 3% / minute, switching will be triggered after 15 seconds. The threshold values ​​for the rate of change of air pressure are as follows: A pressure change rate greater than 0.3 kPa / min for 20 seconds triggers a switchover.

[0028] The duration thresholds for steady-state conditions are as follows: When all operating parameters change less than the steady-state allowable deviation and remain stable for more than 5 minutes, the system defaults to switching to steady-state mode; the adjustable range is 1 minute to 30 minutes, adaptable to different unit models.

[0029] like Figure 3 As shown, when different controlled objects appear one after the other, if the pressure pulsation frequency exceeds the limit, non-steady-state fuel regulation is activated, including: If, after one adjustment, the pressure pulsation frequency band with the same valve, the same adjustment direction, and a higher adjustment priority exceeds the standard before the waiting time t has elapsed, then it is not necessary to wait for the time to end; adjustment should begin immediately for the pressure pulsation frequency band. If, after one adjustment, the pressure pulsation frequency band with the same valve, the same adjustment direction, and a lower adjustment priority exceeds the standard before the waiting time t has elapsed, then the adjustment for the pressure pulsation frequency band will be performed after the waiting time has elapsed. If, after one adjustment, the pressure pulsation frequency band exceeds the standard before the waiting time t has elapsed, even if the same valve is being adjusted, the adjustment direction is opposite, and the adjustment priority is higher, then the adjustment should not wait until the time expires; the adjustment should begin immediately for the pressure pulsation frequency band. If, after one adjustment, the pressure pulsation frequency band exceeds the standard before the waiting time t has elapsed, even if the same valve is adjusted, the adjustment direction is opposite, and the adjustment priority is lower, then the adjustment for the pressure pulsation frequency band will be performed after the waiting time has elapsed.

[0030] Furthermore, the following detailed description is provided in conjunction with specific embodiments: Example 1: Unsteady-state regulation based on load changes: The load change rate thresholds are as follows: 15% to 30% of the rated load, including the period before grid connection and start-up and shutdown, is defined as the low-load stable combustion range: if the load change rate is greater than 2% of the rated load per minute, an unsteady-state switch will be triggered immediately after 5 seconds. 30% to 70% of rated load, the normal peak-shaving range, is defined as the intermediate load range: if the load change rate is >5% of rated load per minute, it will trigger immediately after 10 seconds; if the change rate is >10% of rated load per minute, it will trigger the emergency unsteady mode. 70% to 100% of rated load, rated operating range, defined as basic load range: if the load change rate is >3% of rated load per minute, it will trigger immediately after 10 seconds; if the change rate is >8% of rated load per minute, it will trigger emergency unsteady mode.

[0031] During operation, a gas turbine power plant received a grid dispatch instruction requiring it to increase its output power from 200MW to 280MW within 10 minutes. The load change rate was 8MW / minute, which far exceeded the steady-state allowable deviation threshold, which was set at 2MW / minute.

[0032] The system operating condition identification module detected that the load change rate exceeded the limit and immediately switched the regulation mode from steady state to unsteady state. During the load increase process, the amplitude of the 150Hz frequency band of the combustion chamber pressure pulsation signal rapidly increased from the initial 0.5 bar to 1.2 bar. The safety threshold is 1.0 bar, triggering unsteady state regulation.

[0033] The pressure pulsation analysis module identified an excessive 150Hz frequency band. Based on the valve-frequency band mapping table, it determined that this frequency band was primarily affected by the main fuel valve. The bias value calculation module, based on the deviation between the current pressure pulsation amplitude and the safety threshold, calculated that the main fuel valve opening needed to be reduced by 3%. The bias value management module marked this bias value as a non-steady-state bias value and did not write it into the steady-state bias value matrix.

[0034] The valve control module performed an adjustment, reducing the main fuel valve opening by 3%. After a 30-second waiting period, the pressure pulsation amplitude dropped to 0.8 bar, below the safety threshold, and the unsteady-state adjustment was completed.

[0035] Subsequently, the system initiates the bias rollback mechanism, gradually reducing the unsteady bias value by 3% at a rate of 10% per minute. When the bias rollback reaches 1.5%, the pressure pulsation amplitude rises again to 0.9 bar, reaching the homing point: set at 90% of the safety threshold, i.e., 0.9 bar. The system immediately stops the bias rollback and maintains the bias value at 1.5%.

[0036] Ten minutes later, the load stabilized at 280MW, the rate of change of operating conditions dropped to zero and remained so for 5 minutes, the steady-state confirmation delay was set to 5 minutes, the system determined that it had entered steady-state operating condition, and switched to steady-state regulation mode. Since the non-steady-state bias value reached the return point and stopped during the return process, the system used the current 1.5% bias value as the steady-state bias value and stored it in the operating point corresponding to the 280MW load in the steady-state bias value matrix, thus realizing bias value inheritance.

[0037] Example 2: Non-steady-state regulation based on changes in ambient temperature: Specifically, the threshold for the rate of change of ambient temperature: Normal operating conditions: Temperature change rate > 2℃ per minute, switching is triggered after 10 seconds; Extreme operating conditions, i.e., ambient temperature > 35℃ or < -10℃: temperature change rate > 1℃ per minute, triggering switching after 5 seconds; Step trigger: If the intake air temperature increases by more than 3°C in a single step, it will be triggered immediately.

[0038] During the operation of a certain marine gas turbine, the ambient temperature rapidly decreased from 25℃ to 10℃, with a temperature change rate of 3℃ / minute, exceeding the steady-state allowable deviation threshold, which is set at 2℃ / minute.

[0039] The system detected excessive temperature changes and switched to non-steady-state regulation mode. The temperature drop led to an increase in intake air density, causing the 250Hz and 400Hz frequency bands of the combustion chamber pressure pulsation signal to exceed the limits simultaneously, with amplitudes of 1.1 bar and 0.9 bar respectively, both exceeding the safety threshold of 1.0 bar.

[0040] The pressure pulsation analysis module assigns priorities to the two out-of-range frequency bands: the 250Hz band has a larger amplitude and a lower frequency, so its priority is set to 1; the 400Hz band has its priority set to 2. Based on the valve-frequency band mapping relationship, the 250Hz band is mainly affected by the duty fuel valve, while the 400Hz band is mainly affected by the axial stage valve. Since the two valves are different, they can be adjusted in parallel.

[0041] The system first processes the high-priority 250Hz frequency band, calculating that the opening of the duty fuel valve needs to be increased by 2%. Simultaneously, the system initiates parallel adjustment of the 400Hz frequency band, calculating that the opening of the axial stage valve needs to be reduced by 1.5%. The adjustment actions of the two valves are executed simultaneously without interference.

[0042] Waiting time: Set to 40 seconds, the system continuously monitors pressure pulsations. At the 20th second, a new out-of-range frequency band, 200Hz, with an amplitude of 1.3 bar and a priority of 0, was detected, exceeding the 250Hz band. System comparison revealed that the 200Hz band was also primarily affected by the duty fuel valve, and the adjustment direction was the same as the 250Hz band—increasing the opening. Therefore, the waiting period for the 250Hz band was immediately interrupted, and the system switched to processing the 200Hz band, further increasing the duty fuel valve opening by 1%, for a cumulative increase of 3%.

[0043] After a new waiting period, the pressure pulsations in both the 200Hz and 250Hz frequency bands decreased to below the safety threshold, and the adjustment of the duty fuel valve was completed. At the same time, the adjustment of the axial stage valve was also completed, and the pressure pulsations in the 400Hz frequency band decreased to below the safety threshold.

[0044] Subsequently, the system initiated a revert mechanism for the 3% unsteady-state bias value of the duty fuel valve and the 1.5% unsteady-state bias value of the axial stage valve. During the revert process, neither bias value reached the return holding point and ultimately reverted completely to zero without bias value inheritance.

[0045] Once the temperature stabilizes, the system switches back to steady-state regulation mode and continues to make normal adjustments based on the steady-state bias matrix.

[0046] Example 3: Unsteady-state regulation with simultaneous changes in multiple operating parameters: In addition to the load change rate threshold and the ambient temperature change rate threshold, there is also a humidity change rate threshold; During operation, a gas turbine simultaneously encountered load changes, increasing from 150MW to 200MW at a rate of 5MW / minute, and ambient humidity changes, decreasing from 60% to 40% at a rate of 4% / minute. Both operating parameters exceeded the steady-state allowable deviation threshold.

[0047] The system determined that it had entered a non-steady-state operating condition and switched to non-steady-state regulation mode. The pressure pulsation analysis module identified that three frequency bands—120Hz, 180Hz, and 300Hz—simultaneously exceeded the limit, with amplitudes of 1.2 bar, 1.0 bar, and 0.95 bar, respectively. The system assigned priorities based on amplitude and frequency characteristics: 120Hz had the highest priority, followed by 180Hz, and 300Hz had the lowest priority.

[0048] Based on the valve-frequency band mapping relationship, the 120Hz and 180Hz frequency bands are mainly affected by the main fuel valve, while the 300Hz frequency band is mainly affected by the axial stage valve. The system first processes the 120Hz frequency band and calculates that the main fuel valve opening needs to be reduced by 4%; simultaneously, it processes the 300Hz frequency band in parallel and calculates that the axial stage valve opening needs to be increased by 2%.

[0049] During the waiting period for main fuel valve adjustment, the 180Hz frequency band continued to exceed the limit, but its priority was lower than 120Hz, so the system continued to wait for the adjustment effect of the 120Hz frequency band. After the waiting period ended, the pressure pulsation of the 120Hz frequency band dropped below the safe threshold, and the system switched to processing the 180Hz frequency band, further reducing the main fuel valve opening by 1.5%, for a cumulative reduction of 5.5%.

[0050] Ultimately, the pressure pulsations in all three frequency bands decreased below the safety threshold, and the unsteady-state regulation was completed. The system initiated a rollback mechanism for the 5.5% unsteady-state bias value of the main fuel valve and the 2% unsteady-state bias value of the axial stage valve. During the rollback process, the main fuel valve bias value reached the homing point when it rolled back to 3%, stopped rolling back, and was converted into a steady-state bias value and stored in the bias value matrix; the axial stage valve bias value rolled back completely to zero without any inheritance.

[0051] After the operating conditions stabilize, the system switches back to steady-state regulation mode. The main fuel valve has already included 3% of the inherited bias value in the steady-state bias value matrix at the new operating point, and subsequent steady-state regulation will be fine-tuned based on this.

[0052] In summary, the bias value generated in the non-steady-state adjustment mode is not written into the steady-state bias value matrix. After the adjustment is completed, it gradually returns to zero at a preset rate. If the pressure pulsation reaches the return point during the return process, the return stops and the bias value is converted into a steady-state bias value and stored in the matrix, thus realizing the inheritance of the effective bias value.

[0053] Specifically, the unsteady bias values ​​generated during the adjustment process slowly return to 0, including: The return rates are as follows:

[0054]

[0055] in, Let be the valve bias value at time t. This is the initial bias value at the end of the unsteady-state adjustment. The exponential decay coefficient is... The linear backoff rate.

[0056] The rollback mode is as follows: Dynamically adjust the retreat strategy based on segmented pressure pulsation amplitude: Rapid pullback phase: When the pressure pulsation amplitude is greater than 80% of the warning threshold, a high linear rate is used to quickly pull back to 60% of the initial bias value, with the duration not exceeding 30% of the total pullback time; Smooth transition phase: When the pressure pulsation amplitude is in the range of 30% to 80% of the warning threshold, an exponential decay mode is adopted to return to 70% of the remaining bias value, with the duration accounting for 50% of the total return time; Slow-speed termination phase: When the pressure pulsation amplitude is less than 30% of the warning threshold, a low linear rate is used to retreat until the bias value returns to zero, and the duration accounts for 20% of the total retreat time.

[0057] Specifically, the priority is determined based on the following criteria: Emergency protection level: Pressure pulsation amplitude in any frequency band reaches 90% or more of the trip protection threshold, pulsation amplitude change rate is >50% per second, and pulsation in the low-frequency resonance band exceeds the standard, which can easily cause excessive vibration of the combustion chamber shell. High-risk suppression level: The amplitude of any frequency band pulse reaches 80% to 90% of the alarm threshold, the pulse in the medium frequency thermoacoustic oscillation frequency band exceeds the standard, which has caused the flue gas temperature dispersion to exceed the standard and triggered the alarm twice in the same frequency band within 1 minute. Medium-risk warning level: The pulsation amplitude in any frequency band reaches 30% to 60% of the warning threshold, the pulsation in the high-frequency ablation frequency band continues to exceed the standard, and the pulsation amplitude continues to rise during the load change process; Low-risk stable combustion level: The pulse amplitude in any frequency band reaches 30% to 60% of the warning threshold, the pulse fluctuates slightly without an upward trend, and the flame intensity fluctuates slightly under low load conditions; Optimized adjustment level: Pulsation amplitude is less than 30% of the warning threshold; Specifically, the priority adjustment mechanism is as follows: For every 10% increase in the pulse amplitude of the same frequency band above the alarm threshold, the priority level increases by 1; for every 20% decrease in the alarm threshold, the priority level decreases by 1. If the pulse amplitude continues to rise for more than 3 seconds, the priority level is increased by 1 level; if it continues to fall for more than 5 seconds, the priority level is decreased by 1 level. Under non-steady-state conditions, the priority of all frequency bands is increased by 1 level by default; under emergency non-steady-state / start-stop / low load conditions, the priority is increased by 2 levels by default.

[0058] Valve A regulates pressure pulsation frequency band 2, while valve B regulates pressure pulsation frequency band 4. Currently, the system is in a non-steady-state condition, and pressure pulsation frequency band 2 exceeds the limit. Therefore, the non-steady-state fuel regulator is activated. If, after adjusting pressure pulsation frequency band 2 to exceed the limit, the waiting time t has not elapsed, and pressure pulsation frequency band 4 adjusted by valve B exceeds the limit, valve A will remain stationary while valve B will immediately activate. If the limit is not exceeded after the preset waiting time, both valves will return to their original positions.

[0059] Specifically, when the operating condition changes less than the steady-state allowable deviation over time, after a certain time delay, if the change remains below the steady-state allowable deviation for an extended period, steady-state adjustment is initiated, including: After one adjustment, the unsteady-state regulation becomes steady-state regulation. After a certain period of time t, the object being adjusted no longer exceeds the limit, and the unsteady bias value generated during the unsteady-state regulation process slowly returns to 0. After one adjustment, the unsteady-state regulation becomes steady-state regulation. If the value still exceeds the limit after a certain period of time t, the steady-state regulation will be adjusted one step, and the unsteady-state bias value generated during the adjustment process will slowly return to 0. After one adjustment, the unsteady-state regulation becomes steady-state regulation. If the pressure pulsation frequency band with the same adjustment valve, the same adjustment direction, and a lower adjustment priority exceeds the standard before the waiting time t is reached, then after the waiting time ends, if the pressure pulsation frequency band still exceeds the standard, then steady-state adjustment is performed on the pressure pulsation frequency band. After that, the unsteady-state bias value generated during the unsteady-state regulation adjustment process slowly returns to 0. After one adjustment, the unsteady-state regulation becomes steady-state regulation. If the pressure pulsation frequency band with the same adjustment valve, opposite adjustment direction, and higher adjustment priority exceeds the standard before the waiting time t is reached, then it is not necessary to wait for the time to end. Steady-state adjustment for the pressure pulsation frequency band can be started immediately. After that, the unsteady bias value generated during the unsteady-state regulation adjustment process slowly returns to 0. After one adjustment, the unsteady-state regulation becomes steady-state regulation. If the pressure pulsation frequency band with the same adjustment valve, opposite adjustment direction, and lower adjustment priority exceeds the standard before the waiting time t is reached, the adjustment for the pressure pulsation frequency band will be carried out after the waiting time ends. After that, the unsteady bias value generated during the unsteady-state regulation adjustment process will slowly return to 0. After one adjustment, the unsteady-state regulation becomes steady-state regulation. If the pressure pulsation frequency band regulated by valve B exceeds the limit before the waiting time t is reached, it is not necessary to wait for the time to end. Steady-state regulation is performed immediately. Valve A remains stationary, and valve B immediately moves. After the waiting time ends, the limit is not exceeded. Then, the unsteady-state bias value generated during the unsteady-state regulation process slowly returns to 0. After one adjustment, the unsteady-state regulation becomes steady-state regulation. After a waiting time t, it no longer exceeds the limit. During the slow return of the valve, it reaches the return holding point, and the unsteady-state bias value no longer returns to 0. After the waiting time ends, the unsteady-state bias value is stored as the steady-state bias value in the current bias value matrix.

[0060] In summary, during mode switching, the non-steady-state bias value gradually decreases according to the backoff mechanism, and the steady-state adjustment mechanism takes over the control. If the return point is reached during the backoff process, the non-steady-state bias value is converted into a steady-state bias value to ensure the continuity and stability of the switching.

[0061] In another aspect, the present invention also discloses a computer-readable storage medium storing a computer program, which, when executed by a processor, causes the processor to perform the steps of the method described above.

[0062] In another aspect, the present invention also discloses a computer device, including a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor performs the steps of the method described above.

[0063] In the above embodiments, implementation can be achieved, in whole or in part, through software, hardware, firmware, or any combination thereof. When implemented in software, it can be implemented, in whole or in part, as a computer program product. A computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the flow or function according to the embodiments of this application is generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that integrates one or more available media. The available medium can be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium (e.g., solid-state disk), etc.

[0064] It should be noted that, in this document, relational terms such as "first" and "second" are used merely 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 a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes the element.

[0065] The various embodiments in this specification are described in a related manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, the system embodiments are basically similar to the method embodiments, so the description is relatively simple; relevant parts can be referred to the descriptions of the method embodiments.

[0066] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for unsteady-state regulation of automatic combustion in a gas turbine, characterized in that, include: When the operating conditions change over time and exceed the steady-state allowable deviation, the steady-state control immediately switches to unsteady-state control. Unsteady-state regulation includes: When the object being adjusted remains unchanged or different objects are introduced before and after, the pressure pulsation frequency exceeds the standard, and the non-steady-state fuel regulation is activated. When the operating condition changes less than the steady-state allowable deviation over time, after a certain time delay, if it remains less than the steady-state allowable deviation during the delay period, it will enter steady-state adjustment. The steady-state allowable deviation includes the load change rate threshold, the ambient temperature change rate threshold, the humidity change rate threshold, the air pressure change rate threshold, and the steady-state operating condition duration threshold. When the object being adjusted remains unchanged, if the pressure pulsation frequency exceeds the limit, non-steady-state fuel regulation will be activated, including: After the first adjustment, wait for a certain period of time t before the adjusted object no longer exceeds the limit, and the non-steady bias value generated during the adjustment process slowly returns to 0; If the return point is reached during the return process, the return will stop. If the level still exceeds the limit after a certain period of time following the initial adjustment, then proceed with the next step. If the target object exceeds the limit again during the return process, the return will be stopped and another step will be taken. The bias value is the cumulative value accumulated in real time for each adjustment step during the non-steady-state fuel adjustment process.

2. The unsteady-state regulation method for automatic combustion of a gas turbine according to claim 1, characterized in that: When different controlled objects appear successively, if the pressure pulsation frequency exceeds the standard, non-steady-state fuel regulation will be activated, including: If, after one adjustment step, the pressure pulsation frequency band with the same valve, the same adjustment direction, and a higher adjustment priority exceeds the standard before the waiting time t has elapsed, then it is not necessary to wait for the time to end; adjustment should begin immediately for the pressure pulsation frequency band. If, after one adjustment, the pressure pulsation frequency band with the same valve, the same adjustment direction, and a lower adjustment priority exceeds the standard before the waiting time t has elapsed, then the adjustment for the pressure pulsation frequency band will be performed again after the waiting time has elapsed. If, after one adjustment step, the pressure pulsation frequency band with the same valve adjustment, opposite adjustment direction, and higher adjustment priority exceeds the standard before the waiting time t has elapsed, then the adjustment should not wait for the time to end, but should immediately begin to adjust the pressure pulsation frequency band. If, after one adjustment, the pressure pulsation frequency band exceeds the standard before the waiting time t has elapsed, even though the valve is adjusted in the same direction but with the opposite adjustment direction and a lower adjustment priority, then the adjustment for the pressure pulsation frequency band will be performed after the waiting time has elapsed.

3. The unsteady-state regulation method for automatic combustion of a gas turbine according to claim 2, characterized in that: When the operating condition changes over time beyond the steady-state allowable deviation, the steady-state regulation immediately switches to non-steady-state regulation, including: The load change rate thresholds are as follows: If the load change rate is greater than 2% of the rated load per minute and continues for 5 seconds, an unsteady-state switching will be immediately triggered. The threshold values ​​for the rate of change of ambient temperature are as follows: A switch is triggered if the temperature change rate is greater than 2°C per minute for 10 seconds. The humidity change rate thresholds are as follows: If the relative humidity changes at a rate greater than 3% per minute for 15 seconds, a switch will be triggered. The duration thresholds for steady-state conditions are as follows: A switch is triggered when the rate of change in air pressure exceeds 0.3 kPa per minute and lasts for 20 seconds.

4. The unsteady-state regulation method for automatic combustion of a gas turbine according to claim 3, characterized in that: The unsteady bias value generated during the adjustment process slowly returns to 0, including: The return rate is as follows: in, Let be the valve bias value at time t. This is the initial bias value at the end of the unsteady-state adjustment. The exponential decay coefficient is... The linear backoff rate.

5. The unsteady-state regulation method for automatic combustion of a gas turbine according to claim 4, characterized in that: The priority division is based on the following criteria: Emergency protection level: Pressure pulsation amplitude in any frequency band reaches 90% or more of the trip protection threshold, pulsation amplitude change rate is >50% per second, and pulsation in the low-frequency resonance band exceeds the standard, which can easily cause excessive vibration of the combustion chamber shell. High-risk suppression level: The amplitude of any frequency band pulse reaches 80% to 90% of the alarm threshold, the pulse in the medium frequency thermoacoustic oscillation frequency band exceeds the standard, which has caused the flue gas temperature dispersion to exceed the standard and triggered the alarm twice in the same frequency band within 1 minute. Medium-risk warning level: The pulsation amplitude in any frequency band reaches 30% to 60% of the warning threshold, the pulsation in the high-frequency ablation frequency band continues to exceed the standard, and the pulsation amplitude continues to rise during the load change process; Low-risk stable combustion level: The pulse amplitude in any frequency band reaches 30% to 60% of the warning threshold, the pulse fluctuates slightly without an upward trend, and the flame intensity fluctuates slightly under low load conditions; Optimized adjustment level: Pulsation amplitude is less than 30% of the warning threshold; The priority adjustment mechanism is as follows: For every 10% increase in the pulse amplitude of the same frequency band above the alarm threshold, the priority level increases by 1; for every 20% decrease in the alarm threshold, the priority level decreases by 1. If the pulse amplitude continues to rise for more than 3 seconds, the priority level is increased by 1. If the drop continues for more than 5 seconds, the priority level is reduced by 1. Under non-steady-state conditions, the priority of all frequency bands is increased by 1 level by default; under emergency non-steady-state / start-stop / low load conditions, the priority is increased by 2 levels by default.

6. The unsteady-state regulation method for automatic combustion of a gas turbine according to claim 5, characterized in that: Valve A regulates pressure pulsation frequency band 2, while valve B regulates pressure pulsation frequency band 4. Currently, the system is in a non-steady-state condition, and pressure pulsation frequency band 2 exceeds the limit. Therefore, the non-steady-state fuel regulator is activated. If, after adjusting pressure pulsation frequency band 2 to exceed the limit, the waiting time t has not elapsed, and pressure pulsation frequency band 4 adjusted by valve B exceeds the limit, valve A will remain stationary while valve B will immediately activate. If the limit is not exceeded after the preset waiting time, both valves will return to their original positions.

7. The unsteady-state regulation method for automatic combustion of a gas turbine according to claim 6, characterized in that: When the operating condition changes less than the steady-state allowable deviation over time, after a certain time delay, if the change remains less than the steady-state allowable deviation during the delay period, then steady-state adjustment is initiated, including: After one adjustment, the unsteady-state regulation becomes steady-state regulation. After a certain period of time t, the object being adjusted no longer exceeds the limit, and the unsteady bias value generated during the unsteady-state regulation process slowly returns to 0. After one adjustment, the unsteady-state regulation becomes steady-state regulation. If the value still exceeds the limit after a certain period of time t, the steady-state regulation will be adjusted one step, and the unsteady-state bias value generated during the adjustment process will slowly return to 0. After one adjustment, the unsteady-state regulation becomes steady-state regulation. If the pressure pulsation frequency band with the same adjustment valve, the same adjustment direction, and a lower adjustment priority exceeds the standard before the waiting time t is reached, then after the waiting time ends, if the low-priority pressure pulsation frequency band still exceeds the standard, then steady-state adjustment is performed on the pressure pulsation frequency band. After that, the unsteady-state bias value generated during the unsteady-state regulation adjustment process slowly returns to 0. After one adjustment, the unsteady-state regulation becomes steady-state regulation. If the pressure pulsation frequency band with the same adjustment valve, opposite adjustment direction, and higher adjustment priority exceeds the standard before the waiting time t is reached, then it is not necessary to wait for the time to end. Steady-state adjustment is immediately started for the pressure pulsation frequency band. After that, the unsteady-state bias value generated during the unsteady-state regulation adjustment process slowly returns to 0. After one adjustment, the unsteady-state regulation becomes steady-state regulation. If the pressure pulsation frequency band with the same adjustment valve, opposite adjustment direction, and lower adjustment priority exceeds the standard before the waiting time t is reached, the adjustment for the pressure pulsation frequency band will be carried out after the waiting time ends. After that, the unsteady bias value generated during the unsteady-state regulation adjustment process will slowly return to 0. After one adjustment, the unsteady-state regulation becomes steady-state regulation. If the pressure pulsation frequency band regulated by valve B exceeds the limit before the waiting time t is reached, it is not necessary to wait for the time to end. Steady-state regulation is performed immediately. Valve A remains stationary, and valve B immediately moves. After the waiting time ends, the limit is not exceeded. Then, the unsteady-state bias value generated during the unsteady-state regulation process slowly returns to 0. After one adjustment, the unsteady-state regulation becomes steady-state regulation. After a waiting time t, it no longer exceeds the limit. During the slow return of the valve, it reaches the return holding point, and the unsteady-state bias value no longer returns to 0. After the waiting time ends, the unsteady-state bias value is stored as the steady-state bias value in the current bias value matrix.

8. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it causes the processor to perform the steps of the method as described in any one of claims 1 to 7.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the computer program is executed by the processor, it causes the processor to perform the steps of the method as described in any one of claims 1 to 7.

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