Combustion adjustment method for gas turbine and combustion pressure pulsation monitoring system

Abstract

The application provides a combustion adjustment method and a combustion pressure pulsation monitoring system of a gas turbine, and belongs to the field of gas turbines. The method comprises the following steps: obtaining the combustion pressure pulsation values and flame intensities of each combustor of the gas turbine under different load conditions respectively; under each load condition, judging whether the combustion pressure pulsation values of each combustor exceed the pressure pulsation limit value and whether the flame intensities are lower than the preset limit value; determining the combustor whose combustion pressure pulsation value exceeds the pressure pulsation limit value or whose flame intensity is lower than the preset limit value under each load condition, and reducing or increasing the fuel ratio of the gas turbine combustion system under the corresponding load condition, so that the combustion pressure pulsation values of all combustors under the corresponding load condition are lower than the pressure pulsation limit value and the flame intensities are higher than the preset limit value. The application comprehensively considers indexes such as combustion pressure pulsation and flame intensity, realizes accurate control of the gas turbine combustion system, and provides guarantee for safe, efficient and environmentally-friendly operation of the gas turbine.

Description

Technical Field

[0001] This invention relates to the field of gas turbines, and more specifically to a combustion adjustment method for a gas turbine and a combustion pressure pulsation monitoring system for a gas turbine. Background Technology

[0002] In lean-burn and dry, low-NOx designs, lower pollutant emissions have been achieved by using a lower fuel-air ratio. However, a low fuel-air ratio also makes gas turbines more susceptible to acoustic / thermal coupled pressure oscillations. Although the amplitude of these pressure oscillations may be small, the repeated effects of long-term pressure fluctuations can cause high-cycle fatigue in downstream metal components such as nozzles, cylinder walls, transition parts, and blades, seriously threatening the operational stability of the gas turbine. Therefore, it is particularly important to employ a stable, reliable, and easy-to-use measurement device to monitor combustion pressure pulsations and conduct combustion condition diagnostics.

[0003] Currently, based on the sensor installation location, gas turbine combustion pressure pulsation monitoring systems can be divided into two categories: contact and non-contact. Although contact measurement methods can display a wider frequency bandwidth than non-contact methods, they have very high requirements for the sensor's high-temperature resistance and stability. Therefore, the entire system is expensive, lacks portability, and can only be used on one type of gas turbine.

[0004] Secondly, the combustion process in gas turbines is highly sensitive to environmental conditions, fuel calorific value, Wobbe index, and load variations. Even minor changes caused by external environmental factors and mechanical losses can lead to combustion oscillations, backfire, and flameout. Therefore, the actual operation of gas turbines is subject to numerous limiting factors and has a narrow range of constraints, making precise and detailed control impossible. Summary of the Invention

[0005] The purpose of this invention is to provide a combustion adjustment method and a combustion pressure pulsation monitoring system for gas turbines, which solves the problems of poor convenience in combustion pressure monitoring and the inability to perform detailed and precise control of the gas turbine combustion system in the prior art.

[0006] To achieve the above objectives, embodiments of the present invention provide a combustion adjustment method for a gas turbine, the method comprising:

[0007] The combustion pressure pulsation value and flame intensity of each burner of the gas turbine under different load conditions were obtained respectively;

[0008] Under each load condition, determine whether the combustion pressure pulsation value of each burner exceeds the pressure pulsation limit and whether the flame intensity is lower than the preset limit.

[0009] For each load condition, identify the burners whose combustion pressure pulsation exceeds the pressure pulsation limit or whose flame intensity is lower than the preset limit. Reduce or increase the fuel ratio of the gas turbine combustion system under the corresponding load condition, so that the combustion pressure pulsation of all burners under the corresponding load condition is lower than the pressure pulsation limit and the flame intensity is higher than the preset limit.

[0010] Preferably, after reducing or increasing the fuel ratio of the gas turbine combustion system under the corresponding load condition, so that the combustion pressure pulsation value of all burners is lower than the pressure pulsation limit and the flame intensity is higher than the preset limit under the corresponding load condition, the method further includes: optimizing NOx emissions, including:

[0011] Obtain the NOx and CO emission concentrations of the gas turbine at the nth stage exhaust temperature, where n = {2, 3, ..., N}, and N is the total number of exhaust temperature stages;

[0012] Determine whether the NOx emission concentration is less than the first preset concentration, and determine whether the CO emission concentration is less than the second preset concentration;

[0013] If the NOx emission concentration is less than the first preset concentration and the CO emission concentration is less than the second preset concentration, determine whether the NOx emission concentration is greater than the third preset concentration.

[0014] If the NOx emission concentration is greater than the third preset concentration, the exhaust temperature of the nth stage will be reduced to the exhaust temperature of the (n-1)th stage, so that the NOx emission concentration is less than the third preset concentration.

[0015] Preferably, after reducing the exhaust temperature of the nth stage to the exhaust temperature of the (n-1)th stage, so that the NOx emission concentration is less than the third preset concentration, the method further includes:

[0016] Determine whether the combustion pressure pulsation value of each burner exceeds the pressure pulsation limit;

[0017] If the combustion pressure pulsation value is lower than the pressure pulsation limit, the combustion adjustment is terminated.

[0018] If the combustion pressure pulsation value exceeds the pressure pulsation limit, reduce or increase the current fuel ratio so that the combustion pressure pulsation value is below the pressure pulsation limit.

[0019] Preferably, if the NOx emission concentration exceeds the first preset concentration, or the CO emission concentration exceeds the second preset concentration, the burner is determined to be in an uncontrollable combustion state, and the combustion adjustment is terminated.

[0020] The present invention also provides a combustion pressure pulsation monitoring system for a gas turbine, the system being used to implement the above-described combustion adjustment method for a gas turbine, the system comprising:

[0021] The acquisition module is used to acquire the combustion pressure pulsation value and flame intensity of each burner of the gas turbine under different load conditions;

[0022] The judgment module is used to determine whether the combustion pressure pulsation value of each burner exceeds the pressure pulsation limit and whether the flame intensity is lower than the preset limit under each load condition.

[0023] The adjustment module is used to identify burners whose combustion pressure pulsation value exceeds the pressure pulsation limit or whose flame intensity is lower than the preset limit under each load condition, and to reduce or increase the fuel ratio of the gas turbine combustion system under the corresponding load condition, so that the combustion pressure pulsation value of all burners is lower than the pressure pulsation limit and the flame intensity is higher than the preset limit under the corresponding load condition.

[0024] Preferably, the acquisition module includes:

[0025] Combustion pressure pulsation detection unit is used to detect the combustion pressure pulsation value of the burner;

[0026] Flame intensity detection unit, used to detect the flame intensity of the burner.

[0027] Preferably, the combustion pressure pulsation detection unit includes: a measuring pipeline, a pressure sensor, and a processor;

[0028] The measuring pipeline is connected to the burner and is used to extract the combustion pressure;

[0029] The pressure sensor is installed on the measuring pipeline to detect combustion pressure;

[0030] The processor is electrically connected to the pressure sensor and is used to analyze and process the combustion pressure to obtain the combustion pressure pulsation value of the burner.

[0031] Preferably, it further includes: a continuous emission monitoring unit for continuously and in real time monitoring the flue gas emissions of the gas turbine and acquiring flue gas parameters, including: NOx emission concentration, CO emission concentration, and flue gas temperature.

[0032] Preferably, the measuring pipeline includes: a pressure tap, a three-way valve, a coil, a first ball valve, and a second ball valve;

[0033] The first ball valve is installed on the pressure tapping pipe. The input end of the pressure tapping pipe is connected to the burner, the output end of the pressure tapping pipe is connected to the first end of the three-way valve, the second end of the three-way valve is connected to the input end of the coil, the second ball valve is installed on the output end of the coil, and the pressure sensor is installed in the third end of the three-way valve.

[0034] Preferably, a pressure gauge is installed on the coil.

[0035] Through the above technical solution, the present invention has at least the following technical effects:

[0036] The combustion adjustment method of the present invention comprehensively considers indicators such as combustion pressure pulsation, flame intensity, and exhaust temperature, and can achieve detailed and precise control of the gas turbine combustion system, thus providing a guarantee for the safe, efficient, and environmentally friendly operation of the gas turbine.

[0037] Other features and advantages of the embodiments of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0038] The accompanying drawings are provided to further illustrate embodiments of the present invention and form part of the specification. They are used together with the following detailed description to explain the embodiments of the present invention, but do not constitute a limitation thereof. In the drawings:

[0039] Figure 1 This is a flowchart of a combustion adjustment method for a gas turbine provided in one embodiment of the present invention;

[0040] Figure 2 This is a block diagram of a combustion pressure pulsation monitoring system for a gas turbine provided in one embodiment of the present invention;

[0041] Figure 3 This is a block diagram of the acquisition module of a combustion pressure pulsation monitoring system for a gas turbine provided in one embodiment of the present invention;

[0042] Figure 4 This is a schematic diagram of the combustion pressure pulsation detection unit provided in one embodiment of the present invention.

[0043] Explanation of reference numerals in the attached figures

[0044] 0-Burner; 1-Chassis; 2-Pressure sensor; 3-Processor; 4-Pressure tap; 5-Three-way valve; 6-Coil; 7-First ball valve; 8-Second ball valve; 9-Metal partition; 10-Main pipe; 11-Pressure gauge; 12-Three-way pipe; 13-Continuous emission monitoring unit. Detailed Implementation

[0045] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the scope of the present invention.

[0046] Figure 1 This is a flowchart of a combustion adjustment method for a gas turbine provided in one embodiment of the present invention, as shown below. Figure 1 As shown, a combustion adjustment method for a gas turbine includes:

[0047] Step S101: Obtain the combustion pressure pulsation value and flame intensity of each burner of the gas turbine under different load conditions;

[0048] In this embodiment, the load range is 85MW to 115MW, and combustion adjustments are made for each load condition within this range.

[0049] In this embodiment, before adjusting the combustion of the gas turbine, it is necessary to check and confirm the climatic conditions and measuring point status of the gas turbine, for example:

[0050] The day was not subject to extreme weather conditions such as rain, snow, or fog. Before the start of the fuel adjustment, the ambient temperature, humidity, atmospheric pressure, and other conditions were confirmed to meet the requirements for fuel adjustment.

[0051] Confirm that the CEMS (Continuous Emission Monitoring System) is operating normally and calibrated correctly, and confirm the status of NOx and CO measuring points. If the equipment at the NOx or CO measuring point is unavailable, temporary measuring equipment must be installed. If temporary measuring equipment is used, start the gas turbine. After the gas turbine enters the premixed combustion mode, check and confirm the fuel ratio. Adjust the fuel ratio in 0.5% increments, and stay at each fuel ratio for 5 minutes, record the flue gas data, and calibrate the on-site emission measuring equipment.

[0052] Next, the gas turbine was warmed up for 3 hours under basic load conditions. Emissions were measured in the second hour, and the emission values ​​were recalibrated in the third hour to ensure accurate flue gas measurements.

[0053] After checking and confirming the climate conditions and measurement points of the gas turbine, combustion adjustments were carried out sequentially in the load range of 85MW to 115MW.

[0054] Step S102: Under each load condition, determine whether the combustion pressure pulsation value of each burner exceeds the pressure pulsation limit and whether the flame intensity is lower than the preset limit.

[0055] In this embodiment, the pressure pulsation limit for low-frequency oscillation (frequency range of 30-65Hz) is 1.0 psi, and the pressure pulsation limit for high-frequency oscillation (frequency range of 65-250Hz) is 1.75 psi. Secondly, in the premixed combustion mode of the gas turbine, the higher the flame intensity, the less likely the combustion flame is to be extinguished, but the NOx emission concentration will increase.

[0056] Gas turbines typically have multiple burners. In this embodiment, the gas turbine has 14 burners. The combustion pressure pulsation value and flame intensity of each burner can be collected separately under each load condition, and each burner can be evaluated.

[0057] Step S103: Identify the burners whose combustion pressure pulsation value exceeds the pressure pulsation limit or whose flame intensity is lower than the preset limit under each load condition, and reduce or increase the fuel ratio of the gas turbine combustion system under the corresponding load condition so that the combustion pressure pulsation value of all burners under the corresponding load condition is lower than the pressure pulsation limit and the flame intensity is higher than the preset limit.

[0058] In this embodiment, taking the combustion regulation under a 105MW load condition of the gas turbine as an example, under this load condition, the combustion pressure pulsation of all 14 burners was checked. The test results showed that burners #10 and #11 had instantaneous HT combustion pressure pulsation exceeding 1.75psi. Therefore, the combustion state of burners #10 and #11 was optimized by adjusting the fuel ratio.

[0059] First, modify the maximum fuel ratio FXKSPMMX from 87 to 85, and the fuel ratio FXKSPM from 85.7250 to 85. After adjustment, check the combustion pressure pulsation again. If it is observed that the combustion pressure pulsation has increased significantly and there is a dynamic over-limit situation, that is, the combustion pressure pulsation exceeds the specified value of 1.75psi, then the adjustment does not meet the requirements and needs to be adjusted again.

[0060] Secondly, the maximum fuel ratio FXKSPMMX was restored to the initial value (85→86). FXKSPM[2] changed from 85.5→85.7, and FXKSPM[3] changed from 85.75→86. Then the fuel ratio FXKSPM changed from 85.7250→85.9700. The combustion pulsation was observed to be slightly smaller overall, NOx emissions were normal, CO was normal, flame intensity was stable, and the overall parameters were quite good.

[0061] Finally, after modifying FXKSPM[2] and FXKSPM[3], the load was first increased from 105MW to 110MW, and then the load was slowly reduced to 100MW. After 10 minutes, the combustion pulsation in the premixed combustion mode was observed. It was found that the combustion pressure pulsation value was stably maintained in the range of 0.7psi to 1.2psi. Compared with the dynamic curve of combustion pulsation in the entire premixed section before adjustment (0.9psi to 1.5psi), the overall operation was good.

[0062] In this embodiment, since the heat release rate and combustion pressure pulsation are coupled and influence each other, on the one hand, the combustion pressure pulsation value must always be within the limit and retain a certain margin; on the other hand, the fluctuation of combustion pressure pulsation over time should not be too large. The time kurtosis TK can be used to comprehensively evaluate the combustion stability.

[0063]

[0064] In the formula, n is the number of combustion pressure pulsations collected within time T, and p i Let be the instantaneous combustion pressure pulsation value (peak-to-peak value) at time i, and p be the average of all combustion pressure pulsation values ​​(peak-to-peak values) over time T.

[0065] When TK approaches 3.0, the combustion pressure pulsation generally exhibits a normal distribution, indicating that combustion is in a stable state. However, when combustion oscillations occur at a certain characteristic frequency, TK converges to 1.5, and the combustion pressure pulsation at this point typically displays a bimodal distribution.

[0066] As a further optimization of this embodiment, since the NOx emission concentration in the flue gas also increases after the flame intensity is increased, the fuel ratio of the gas turbine combustion system is reduced or increased under the corresponding load condition. This ensures that the combustion pressure pulsation value of all burners is lower than the pressure pulsation limit and the flame intensity is higher than the preset limit under the corresponding load condition. That is, in premixed combustion mode, after adjusting the fuel ratio to the optimal state, NOx emissions are optimized, including:

[0067] Step a01: Obtain the NOx and CO emission concentrations of the gas turbine at the nth stage exhaust temperature, where n = {2, 3, ..., N}, and N is the total number of exhaust temperature stages. For example, if there are 4 exhaust temperature stages, the first stage exhaust temperature is 1070℉, the second stage exhaust temperature is 1080℉, the third stage exhaust temperature is 1090℉, and the fourth stage exhaust temperature is 1100℉.

[0068] In this embodiment, a CEMS (Continuous Flue Gas Monitoring System) can be used to collect NOx and CO emission concentrations, or a temporary measuring device can be used to collect NOx and CO emission concentrations.

[0069] Step a02: Determine whether the NOx emission concentration is less than a first preset concentration and whether the CO emission concentration is less than a second preset concentration. In this embodiment, the first preset concentration is preferably 30 mg / m³. 3 The second preset concentration is preferably 20 mg / m³. 3 .

[0070] Step a03: If the NOx emission concentration is less than the first preset concentration and the CO emission concentration is less than the second preset concentration, determine whether the NOx emission concentration is greater than the third preset concentration. In this embodiment, the third preset concentration is preferably 18 mg / m³. 3 .

[0071] In this embodiment, if the NOx emission concentration exceeds the first preset concentration or the CO emission concentration exceeds the second preset concentration, the burner is in an uncontrollable combustion state and cannot be adjusted according to the combustion adjustment steps of the present invention. The combustion state of the gas turbine needs to be re-determined.

[0072] Step a04: If the NOx emission concentration is greater than the third preset concentration, reduce the exhaust temperature of the nth stage to the exhaust temperature of the (n-1)th stage, so that the NOx emission concentration is less than the third preset concentration; for example, reduce the exhaust temperature of the 4th stage to the exhaust temperature of the 3rd stage, that is, from 1100℉ to 1090℉; in this embodiment, when the NOx emission concentration is less than the third preset concentration, it means that the NOx emission concentration is low under the condition of exhaust temperature, and there is no need to optimize it.

[0073] After reducing the exhaust temperature of stage n to the exhaust temperature of stage n-1, so that the NOx emission concentration is less than the third preset concentration, the combustion state needs to be adjusted again according to the combustion pressure pulsation. This method also includes:

[0074] Determine whether the combustion pressure pulsation value exceeds the pressure pulsation limit;

[0075] If the combustion pressure pulsation value does not exceed the pressure pulsation limit, the combustion adjustment ends;

[0076] If the combustion pressure pulsation value exceeds the pressure pulsation limit, adjust the current fuel ratio (adjust the current fuel ratio according to the adjustment method in step S103) so that the combustion pressure pulsation value is lower than the pressure pulsation limit.

[0077] After the above combustion adjustments, under basic load conditions, the peak value of combustion pressure pulsation decreased from 0.9psi to 1.5psi to 0.7psi to 1.2psi, and the optimized gas turbine combustion oscillation was reduced by 20% to 33%.

[0078] After the above combustion adjustments, under basic load conditions, the main pollutant NOx decreased significantly, by approximately 18%, to 11.6 mg / m³. 3 .

[0079] After the above combustion adjustments, under basic load conditions, the main pollutant CO decreased slightly by about 8%, reaching 14 mg / m³. 3 .

[0080] After the above combustion adjustments, under basic load conditions, the flame intensity in Zone 2 decreases by approximately 3-6 percentage points, and the intensities of the four flame detector probes in Zone 2 decrease to 46%, 46%, 27%, and 63%, respectively. Since the reduction in flame intensity is small, there is still a considerable margin, and therefore, flame stability will not be affected.

[0081] The combustion adjustment method of the present invention comprehensively considers indicators such as combustion pressure pulsation, flame intensity, and exhaust temperature, enabling detailed and precise control of the steam turbine and providing a guarantee for the safe, efficient, and environmentally friendly operation of the gas turbine.

[0082] Figure 2 This is a block diagram of a combustion pressure pulsation monitoring system for a gas turbine according to one embodiment of the present invention, as shown below. Figure 2 As shown, the system is used to implement the above-described combustion adjustment method for a gas turbine, and the system includes:

[0083] The acquisition module is used to acquire the combustion pressure pulsation value and flame intensity of each burner of the gas turbine under different load conditions;

[0084] The judgment module is used to determine whether the combustion pressure pulsation value of each burner exceeds the pressure pulsation limit and whether the flame intensity is lower than the preset limit under each load condition.

[0085] The adjustment module is used to identify burners whose combustion pressure pulsation value exceeds the pressure pulsation limit or whose flame intensity is lower than the preset limit under each load condition, and to reduce or increase the fuel ratio of the gas turbine combustion system under the corresponding load condition, so that the combustion pressure pulsation value of all burners under the corresponding load condition is lower than the pressure pulsation limit and the flame intensity is higher than the preset limit.

[0086] As a further optimization of this embodiment, the acquisition module includes:

[0087] Combustion pressure pulsation detection unit is used to detect the combustion pressure pulsation value of burner 0;

[0088] The flame intensity detection unit is used to detect the flame intensity of the burner 0. In this embodiment, the flame intensity detection unit can be an XHT flame detector.

[0089] As a further optimization of this embodiment, such as Figure 3 As shown, the combustion pressure pulsation detection unit includes: a measuring pipeline, a pressure sensor 2, a processor 3, and a chassis 1. The measuring pipeline, pressure sensor 2, and processor 3 are all installed inside the chassis 1.

[0090] The measuring pipeline is connected to the burner 0 and is used to extract the combustion pressure;

[0091] The pressure sensor 2 is installed on the measuring pipeline and is used to detect combustion pressure;

[0092] The processor 3 is electrically connected to the pressure sensor 2 and is used to analyze and process the combustion pressure to obtain the combustion pressure pulsation value of the burner 0.

[0093] In this embodiment, the combustion pressure pulsation detection unit has multiple measurement pipelines. Each measurement pipeline can lead out the combustion pressure of a burner 0. A pressure sensor 2 is installed on each measurement pipeline to detect the combustion pressure of each pipeline. The combustion pressures detected by all pressure sensors 2 are simultaneously uploaded to the processor 3 for analysis and processing to obtain the combustion pressure pulsation value of each burner 0. Secondly, two pressure sensors 2 can be installed on each measurement pipeline, with one pressure sensor 2 serving as a backup.

[0094] Specifically, such as Figure 4 As shown, each of the aforementioned measuring pipelines includes: a pressure tap 4, a three-way valve 5, a coil 6, a first ball valve 7, and a second ball valve 8;

[0095] The first ball valve 7 is installed on the pressure tapping pipe 4. The input end of the pressure tapping pipe 4 is connected to the burner 0. The output end of the pressure tapping pipe 4 is connected to the first end of the three-way valve 5. The second end of the three-way valve 5 is connected to the input end of the coil 6. The second ball valve 8 is installed on the output end of the coil 6. The pressure sensor 2 is installed in the third end of the three-way valve 5.

[0096] In this embodiment, both the pressure tapping tube 4 and the coil 6 are made of copper tubes with an inner diameter of 4mm and an outer diameter of 6mm. The length of the coil 6 is 15 meters, and the annular coil 6 has a diameter of 400mm and is coiled 12 times. The coils 6 of each measuring pipeline are separated by metal partitions 9. The pipeline in front of the coil 6 is arranged at a high position, and the pipeline behind the coil 6 is arranged at a low position. Due to the setting of the coil 6, the pressure wave, after entering the coil 6, will propagate forward almost continuously without reflection, thereby avoiding resonance, eliminating shock waves (compression waves with abrupt changes on the wavefront), improving the frequency characteristics of the entire device, and effectively reducing measurement errors.

[0097] The pressure sensor 2 is connected to the third end of the three-way valve 5 by a thread. The specific dimensions of the thread of the pressure sensor 2 are as follows: the thread pitch diameter is 9.525 mm, the thread pitch is 1.058 mm, the thread is fine, the accuracy class is 3, and the insertion depth of the sensor thread is 8.636 mm.

[0098] In this embodiment, the processor 3 and the pressure sensor 2 are connected via a high-fidelity cable. The processor 3 converts the analog voltage signal output by the sensor into a digital signal using an analog-to-digital converter (AD converter). The processor 3 then plots a waveform of the combustion pressure pulsation value based on the digital signal. Next, the processor 3 performs a Fourier transform on the waveform of the combustion pressure pulsation value, and outputs a frequency domain waveform of the combustion pressure pulsation after performing a Fourier transform on the time domain waveform. The output indicators are more intuitive and visual, which is more conducive to researchers' data post-processing and combustion state analysis.

[0099] As a further optimization of this embodiment, the output end of the coil 6 is connected to the main pipe 10, and a pressure gauge 11 is installed on the main pipe 10. The pressure gauge 11 is a local pressure gauge with a range of 5MPa. Under normal measurement conditions, the first ball valve 7 is open and the second ball valve 8 is closed. The pressure gauge 11 is installed after the second ball valve 8 to measure the total pressure value of combustion.

[0100] In this embodiment, by opening the second ball valve 8 and the first ball valve 7, a forward purging function can be achieved, which purges the condensate in the pipeline to the outside. During the monitoring of combustion pressure pulsation of the gas turbine, it is no longer necessary to connect an external nitrogen source for pipeline purging, and there is no need to repeatedly disassemble and reassemble valves or pipelines.

[0101] As a further optimization of this embodiment, it also includes: a continuous emission monitoring unit 13 for continuously and in real time monitoring the flue gas emissions of the gas turbine and acquiring flue gas parameters. In this embodiment, a three-way pipe 12 can be connected to the pressure tapping pipe 4. The three-way pipe 12 is located between the first ball valve 7 and the burner 0. The acquisition end of the continuous emission monitoring unit 13 is connected to one end of the three-way pipe 12. The flue gas parameters include: NOx emission concentration, CO emission concentration, and flue gas temperature.

[0102] The combustion pressure pulsation detection unit of the monitoring system of the present invention has the advantages of simple structure, comprehensive functions, and portability.

[0103] The optional embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the embodiments of the present invention are not limited to the specific details in the above embodiments. Within the scope of the technical concept of the embodiments of the present invention, various simple modifications can be made to the technical solutions of the embodiments of the present invention, and these simple modifications all fall within the protection scope of the embodiments of the present invention.

[0104] It should also be noted that the various specific technical features described in the above embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the embodiments of the present invention will not describe the various possible combinations separately.

[0105] Those skilled in the art will understand that all or part of the steps in the methods of the above embodiments can be implemented by a program instructing related hardware. This program is stored in a storage medium and includes several instructions to cause a microcontroller, chip, or processor to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as a USB flash drive, a portable hard drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0106] Furthermore, various different implementations of the present invention can be combined arbitrarily, as long as they do not violate the spirit of the present invention, they should also be regarded as the content disclosed in the present invention.

Claims

1. A combustion adjustment method for a gas turbine, characterized in that, The method includes: The combustion pressure pulsation value and flame intensity of each burner of the gas turbine under different load conditions were obtained respectively; Under each load condition, determine whether the combustion pressure pulsation value of each burner exceeds the pressure pulsation limit and whether the flame intensity is lower than the preset limit. To identify burners whose combustion pressure pulsation value exceeds the pressure pulsation limit or whose flame intensity is lower than the preset limit under each load condition, the fuel ratio of the gas turbine combustion system under the corresponding load condition is reduced or increased so that the combustion pressure pulsation value of all burners under the corresponding load condition is lower than the pressure pulsation limit and the flame intensity is higher than the preset limit. The method further includes: Optimization of NOx emissions from gas turbines includes: Obtain the NOx and CO emission concentrations of the gas turbine at the nth stage exhaust temperature, where n = {2, 3, ..., N}, and N is the total number of exhaust temperature stages. Determine whether the NOx emission concentration is less than the first preset concentration, and determine whether the CO emission concentration is less than the second preset concentration; If the NOx emission concentration is less than the first preset concentration and the CO emission concentration is less than the second preset concentration, determine whether the NOx emission concentration is greater than the third preset concentration. If the NOx emission concentration is greater than the third preset concentration, the exhaust temperature of the nth stage will be reduced to the exhaust temperature of the (n-1)th stage, so that the NOx emission concentration is less than the third preset concentration.

2. The combustion adjustment method for a gas turbine according to claim 1, characterized in that, After reducing the exhaust temperature of stage n to the exhaust temperature of stage n-1, so that the NOx emission concentration is less than the third preset concentration, the process also includes: Determine whether the combustion pressure pulsation value of each burner exceeds the pressure pulsation limit; If the combustion pressure pulsation value of each burner is lower than the pressure pulsation limit, the combustion adjustment is terminated. If the combustion pressure pulsation value of the burner is determined to exceed the pressure pulsation limit, the current fuel ratio of the gas turbine combustion system is reduced or increased so that the combustion pressure pulsation value of all burners is lower than the pressure pulsation limit.

3. The combustion adjustment method for a gas turbine according to claim 1, characterized in that, If the NOx emission concentration exceeds the first preset concentration, or the CO emission concentration exceeds the second preset concentration, the burner is determined to be in an uncontrollable combustion state, and the combustion adjustment is terminated.

4. A combustion pressure pulsation monitoring system for a gas turbine, said system being used to implement the combustion adjustment method for the gas turbine according to any one of claims 1-3, characterized in that, The system includes: The acquisition module is used to acquire the combustion pressure pulsation value and flame intensity of each burner of the gas turbine under different load conditions; The judgment module is used to determine whether the combustion pressure pulsation value of each burner exceeds the pressure pulsation limit and whether the flame intensity is lower than the preset limit under each load condition. The adjustment module is used to identify burners whose combustion pressure pulsation value exceeds the pressure pulsation limit or whose flame intensity is lower than the preset limit under each load condition, and to reduce or increase the fuel ratio of the gas turbine combustion system under the corresponding load condition, so that the combustion pressure pulsation value of all burners is lower than the pressure pulsation limit and the flame intensity is higher than the preset limit under the corresponding load condition.

5. The combustion pressure pulsation monitoring system for a gas turbine according to claim 4, characterized in that, The acquisition module includes: Combustion pressure pulsation detection unit is used to detect the combustion pressure pulsation value of the burner; Flame intensity detection unit, used to detect the flame intensity of the burner.

6. The combustion pressure pulsation monitoring system for a gas turbine according to claim 5, characterized in that, The combustion pressure pulsation detection unit includes: a measuring pipeline, a pressure sensor (2), and a processor (3); The measuring pipeline is connected to the burner and is used to extract the combustion pressure; The pressure sensor (2) is installed on the measuring pipeline to detect combustion pressure; The processor (3) is electrically connected to the pressure sensor (2) and is used to analyze and process the combustion pressure to obtain the combustion pressure pulsation value of the burner.

7. The combustion pressure pulsation monitoring system for a gas turbine according to claim 5, characterized in that, Also includes: The continuous emission monitoring unit (13) is used to continuously and in real time monitor the flue gas emissions of the gas turbine and obtain flue gas parameters; The flue gas parameters include: NOx emission concentration, CO emission concentration, and flue gas temperature.

8. The combustion pressure pulsation monitoring system for a gas turbine according to claim 6, characterized in that, The measuring pipeline includes: pressure tap (4), three-way valve (5), coil (6), first ball valve (7), and second ball valve (8); The first ball valve (7) is installed on the pressure tapping pipe (4). The input end of the pressure tapping pipe (4) is connected to the burner. The output end of the pressure tapping pipe (4) is connected to the first end of the three-way valve (5). The second end of the three-way valve (5) is connected to the input end of the coil (6). The second ball valve (8) is installed on the output end of the coil (6). The pressure sensor (2) is installed inside the third end of the three-way valve (5).

9. The combustion pressure pulsation monitoring system for a gas turbine according to claim 8, characterized in that, A pressure gauge (11) is installed on the coil (6).

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