A combustion diagnosis device and method suitable for gas turbine

Abstract

The present invention discloses a combustion diagnosis device and method suitable for a gas turbine, the device comprising an operating condition parameter module, an initial state data acquisition module, a TDLAS combustion state parameter monitoring module, a combustion criterion storage module and a combustion state diagnosis module. During operation, the operating condition parameter module determines the operating condition of the combustion chamber, the initial state parameter acquisition module acquires parameters such as the initial state of the combustion chamber of the gas turbine; the TDLAS combustion state monitoring module monitors state parameters such as the temperature, pressure pulsation and H2O component concentration of the combustion chamber; the combustion diagnosis module compares and analyzes the combustion chamber state parameters acquired by the TDLAS combustion monitoring module, the combustion state reference information stored in the combustion criterion storage module and the combustion chamber initial state information, and diagnoses and outputs the combustion state of the combustion chamber according to the combustion diagnosis logic. The present invention can accurately locate the faulty combustion chamber, simplify the combustion state monitoring system of the in-service gas turbine, and improve the accuracy of combustion state monitoring diagnosis.

Description

Technical Field

[0001] The present invention belongs to the technical field of gas turbines, and in particular relates to a combustion diagnosis device and method suitable for gas turbines. Background Art

[0002] Gas turbine combustion monitoring and diagnosis mainly obtains the combustion state parameters of the combustion chamber through effective monitoring equipment, diagnoses the combustion state of the combustion chamber in combination with corresponding diagnostic criteria, and is responsible for feeding back the combustion diagnosis results to the gas turbine control system.

[0003] In-service gas turbines mainly monitor the temperature at the turbine outlet through thermocouples, the pressure pulsation sensor monitors the pressure pulsation at the cold end of the combustion chamber, and the flame detector monitors the flame luminescence in the combustion chamber, and performs gas turbine combustion fault diagnosis based on the corresponding combustion diagnosis criteria. First, since the high-temperature gas at the combustion chamber outlet will deflect after passing through the turbine and other rotating parts, the combustion monitoring and diagnosis method of the in-service gas turbine cannot accurately diagnose which combustion chamber has a combustion overtemperature fault by referring to the turbine outlet temperature. In addition, since the combustion chamber outlet temperature is inaccurate when the turbine outlet temperature is reversed, as well as the cold end monitoring, the accuracy of the combustion monitoring and diagnosis of the in-service gas turbine is further reduced. Secondly, the combustion monitoring and diagnosis method of the in-service gas turbine needs to integrate and process the multi-source and multi-type real-time signals of dozens of thermocouples at the turbine outlet, dozens of pressure pulsation sensors at the cold end of the combustion chamber, and multiple flame detectors. The data volume is large and relatively complex, which invisibly increases the diagnostic error of the in-service gas turbine and reduces the accuracy of the combustion monitoring and diagnosis. In order to improve the accuracy of combustion fault monitoring and diagnosis of gas turbines and reduce the complexity of the method, a combustion diagnosis device and method suitable for gas turbines can be developed based on tunable laser absorption spectroscopy (TDLAS). Summary of the invention

[0004] In order to solve the problems of complex combustion monitoring and diagnosis systems and inaccurate combustion state monitoring and diagnosis of in-service gas turbines, the present invention provides a combustion diagnosis device and method suitable for gas turbines. The method can monitor the combustion temperature, combustion stability and H2O concentration of the gas turbine, and can realize fault diagnosis of gas turbine combustion overtemperature, combustion stability and ignition.

[0005] The present invention is achieved through the following technical solutions:

[0006] A combustion diagnosis device suitable for a gas turbine, comprising an operating condition parameter module, an initial state data acquisition module, a TDLAS combustion state parameter monitoring module, a combustion criterion storage module and a combustion state diagnosis module;

[0007] The operating condition parameter module is used to obtain the gas turbine operating condition parameters to determine the operating condition of the combustion chamber, and is connected to the combustion criterion storage module and the combustion state diagnosis module; the initial state data acquisition module is used to obtain the initial state parameters of the combustion chamber, and is connected to the combustion state diagnosis module; the combustion criterion storage module is used to store the combustion chamber diagnosis criterion, and is connected to the combustion state diagnosis module; the combustion diagnosis module diagnoses the combustion state based on the combustion diagnosis logic, and sends the combustion chamber combustion state word to the gas turbine control system.

[0008] A combustion diagnosis method applicable to a gas turbine comprises the following steps:

[0009] Step 1: Obtain the gas turbine IGV angle, fuel flow and temperature, and gas turbine load to determine the gas turbine operating conditions;

[0010] Step 2: According to the operating condition of the gas turbine, a combustion state diagnosis criterion of the gas turbine combustion chamber is obtained, including temperature reference information, H2O concentration reference information and pressure reference information of the gas turbine combustion chamber under the operating condition;

[0011] Step 3: Obtain atmospheric humidity and convert it into initial H2O concentration of the gas turbine combustion chamber; obtain the compressor exhaust temperature and exhaust pressure and use them as the initial temperature and pressure of the gas turbine combustion chamber;

[0012] Step 4: Use the TDLAS combustion monitoring module to obtain the combustion temperature, combustion chamber pressure and combustion state parameters of the combustion chamber H2O concentration, and convert the combustion pressure into pressure pulsation frequency and amplitude through fast Fourier transform;

[0013] Step 5: Compare and analyze the initial H2O concentration of the combustion chamber and the obtained real-time H2O concentration of the combustion chamber, compare and analyze the initial temperature of the combustion chamber and the obtained real-time combustion temperature of the combustion chamber, diagnose whether there is flame in the combustion chamber according to the combustion diagnosis logic, diagnose the ignition state of the combustion chamber, and send out ignition success and combustion chamber no flame ignition failure signals according to the diagnosis results;

[0014] Step 6: Compare and analyze the initial temperature of the combustion chamber, the real-time temperature of the combustion chamber, and the combustion temperature reference information in the combustion diagnosis criterion, diagnose the combustion chamber temperature according to the combustion diagnosis logic, and issue a normal combustion temperature, a high combustion temperature warning, and a combustion temperature over-temperature trip signal according to the diagnosis result;

[0015] Step 7: Compare and analyze the initial pressure of the combustion chamber, the obtained combustion chamber pressure pulsation information, and the combustion pressure reference information in the combustion diagnosis criterion, diagnose the combustion stability according to the combustion diagnosis logic, and issue combustion stability, combustion pressure pulsation high warning and combustion instability trip signal according to the diagnosis result.

[0016] A further improvement of the present invention is that the IGV angle, fuel flow and temperature, and engine load parameters in step 1 can be obtained from the gas turbine control system and stored in the operating condition parameter storage module.

[0017] A further improvement of the present invention is that the temperature reference information of the gas turbine combustion chamber described in the combustion state diagnosis criterion of the gas turbine combustion chamber in step 2 at least includes an array T of normal ranges of the combustion temperature of the combustion chamber under different working conditions. Z , warning value T C,10 And the alarm value T C,20 The stored combustion chamber pressure reference information includes the natural acoustic frequency P of the combustion chamber components. HC,0 , the warning value P of the combustion chamber pressure pulsation amplitude under different working conditions AC,10 and trip value P AC,20 , and the combustion state diagnosis criteria under different operating conditions of the gas turbine combustion chamber are stored in the combustion criterion diagnosis module.

[0018] A further improvement of the present invention is that in step 3, the existing atmospheric humidity monitoring equipment of the gas turbine is used to obtain and convert it into the initial H2O concentration D of the gas turbine combustion chamber. H2O,0 ; Use the existing compressor exhaust temperature and exhaust pressure equipment of the gas turbine to obtain and use it as the initial temperature T of the gas turbine combustion chamber C,0 and initial pressure P C,0 , and the data is stored in the combustion chamber initial state acquisition module.

[0019] A further improvement of the present invention is that the TDLAS combustion monitoring module in step 4 can emit two lasers that can be absorbed by H2O, which are single-mode lasers with wavelengths between 1260nm and 1650nm, and the spectral line intensity values ​​of the two lasers at 450°C to 1800°C are not much different;

[0020] The TDLAS combustion monitoring module is used to monitor the combustion flow field parameters near the exit of the transition section of the combustion chamber. It analyzes the light intensity change information of the laser absorption spectrum and converts it into the temperature value T of the flow field to be measured in the combustion chamber according to the single-value conversion formula between light intensity and temperature. C,t ; By analyzing the one-to-one correspondence between the broadening of the absorption spectrum signal and the pressure, it is converted into the pressure value P of the flow field to be measured in the combustion chamber C,t , and then perform FFT conversion on the flow field pressure to obtain the pressure pulsation frequency P of the flow field to be measured in the combustion chamber HC,t and the corresponding amplitude P AC,t Analyze the line type and second harmonic peak information of the laser absorption spectrum signal, and obtain the H2O concentration D of the flow field to be measured in the combustion chamber based on the corresponding relationship between the component concentration and the second harmonic peak, combined with the combustion temperature and combustion pressure information. H2O,t .

[0021] A further improvement of the present invention is that in step 5, the H2O concentration D of the combustion chamber provided by the TDLAS monitoring module is compared and analyzed. H2O,t The H2O concentration D stored in the combustion chamber initial state acquisition module H2O,Z0 , and compare and analyze the combustion chamber temperature T provided by the TDLAS monitoring module C,t The initial temperature T of the combustion chamber stored in the combustion initial state parameter acquisition module C,0 , based on the combustion diagnosis logic, the combustion chamber ignition status is diagnosed and the combustion chamber ignition success and ignition failure information is sent to the gas turbine control system.

[0022] A further improvement of the present invention is that in step 6, the initial temperature T of the combustion chamber obtained by comparing and analyzing the initial state acquisition module is C,0 , the combustion chamber temperature T provided by the TDLAS monitoring module C,t The early warning value T of the combustion chamber combustion temperature under different working conditions stored in the combustion diagnosis criterion storage module C,10 And the alarm value T C,20 , diagnose the combustion chamber temperature status according to the combustion diagnosis logic, and send the combustion status information of normal combustion temperature, high combustion temperature and over-temperature combustion temperature to the gas turbine control system.

[0023] A further improvement of the present invention is that in step 7, by comparing and analyzing the combustion chamber pressure pulsation frequency P provided by the TDLAS monitoring module HC,t and the corresponding amplitude P AC,t The combustion chamber pressure reference information stored in the combustion diagnosis criterion storage module includes the natural acoustic frequency P of the combustion chamber components under different working conditions. HC,0 , the warning value P of pressure pulsation amplitude and frequency AC,10 and trip value P AC,20 , diagnose the combustion stability of the combustion chamber according to the combustion diagnosis logic, and send combustion pressure pulsation stability, combustion instability warning and combustion instability trip combustion status information to the gas turbine control system.

[0024] A further improvement of the present invention is that the combustion diagnosis logic in the combustion diagnosis method applicable to the gas turbine is as follows:

[0025] If T Ct –T C0 ≥0 and D H2O,t –D H2O,0 >0, indicating that there is continuous flame in the combustion chamber, and the combustion diagnosis module outputs the combustion chamber ignition success and continuous flame status word;

[0026] If D H2O,t –D H2O,0≤0, indicating that there is no continuous flame in the combustion chamber, and the combustion diagnosis module outputs the combustion chamber ignition failure and the state word of no continuous flame;

[0027] If T C,t -T C,0 >0 and T C,t –T C,10 <0, indicating that the combustion chamber temperature is normal, and the combustion diagnosis module issues a combustion chamber temperature normal status word;

[0028] If T C,t -T C,0 >0 and T C,t –T C,10 ≥0 and T C,t –T C,20 <0, indicating that the combustion chamber combustion temperature is high and close to the combustion chamber temperature upper limit, and the combustion diagnosis module issues a high combustion chamber temperature warning status word;

[0029] If T C,t -T C,0 >0 and T C,t –T C,20 ≥0, indicating that the combustion chamber temperature exceeds the safe operating range of the combustion chamber, and the combustion diagnosis module issues a combustion over-temperature alarm status word;

[0030] If |P HC,t -P HC,0 |<50Hz, indicating that the combustion chamber pressure pulsation frequency is close to the combustion chamber natural frequency, and the combustion chamber is very likely to resonate. The combustion diagnosis system issues a combustion chamber resonance status word, and the engine trips;

[0031] If |P HC,t -P HC,0 |≥50Hz, and P AC,t -P AC,10 <0, indicating that the combustion chamber pressure pulsation frequency and pressure pulsation amplitude are both within the combustion safety and stability range, the combustion chamber combustion is stable, and the combustion diagnosis module outputs the combustion stability state word;

[0032] If |P HC,t -P HC,0 |≥50Hz, and P AC,t -P AC,10 ≥0 and P AC,t -P AC,20 <0, indicating that the combustion chamber pressure pulsation frequency is within the safe range, but the combustion chamber pressure pulsation amplitude is close to the safety upper limit, and the combustion diagnosis module issues a combustion pressure pulsation warning status word;

[0033] If |P HC,t -P HC,0 |≥50Hz, and P AC,t -PAC,20 ≥0, indicating that the combustion chamber pressure pulsation frequency is within the safe range, but the combustion chamber pressure pulsation amplitude exceeds the combustion chamber pressure pulsation amplitude safety upper limit, and the combustion diagnosis module issues a combustion pressure pulsation high alarm status word.

[0034] The present invention has at least the following beneficial technical effects:

[0035] The present invention provides a combustion diagnosis device and method suitable for a gas turbine. It does not need to process and analyze the measurement data of multiple monitoring devices measuring components at one time, and does not introduce measurement errors caused by multiple measuring components. It can simplify the combustion state monitoring data processing flow of in-service gas turbines and improve the accuracy of combustion state monitoring diagnosis.

[0036] Furthermore, the present invention provides a combustion diagnosis device and method suitable for a gas turbine. Without contacting the high-temperature combustion gas in the combustion chamber of the gas turbine, the combustion state parameters such as the combustion flow field temperature, pressure and H2O concentration can be directly obtained by processing and analyzing the laser absorption spectrum signal, thereby avoiding the monitoring and diagnosis errors caused by the introduction of empirical formulas to reversely infer the combustion temperature and H2O concentration of the in-service gas turbine.

[0037] Furthermore, the present invention provides a combustion diagnosis device and method suitable for a gas turbine, wherein the TDLAS combustion monitoring and diagnosis module can replace the combustion temperature monitoring system arranged near the turbine outlet, the flame detection system arranged near the combustion chamber nozzle, and the pressure pulsation monitoring system of the in-service gas turbine, thereby avoiding data interaction between multiple systems, improving the measurement accuracy of the gas turbine combustion state parameters, and simplifying the complexity of the existing gas turbine combustion state monitoring system.

[0038] Furthermore, the present invention provides a combustion diagnosis device and method suitable for a gas turbine. It only needs to compare and analyze the initial state parameters of the combustion chamber obtained by the initial state data acquisition module, the combustion chamber state parameters obtained in real time by the TDLAS combustion state parameter monitoring module, and the combustion chamber temperature reference value, H2O concentration reference value, and pressure reference value under different working conditions stored in the combustion criterion storage module, so as to diagnose the combustion state of the gas turbine combustion chamber, and to a certain extent, it can simplify the combustion state diagnosis logic of the gas turbine combustion chamber; and when a combustion failure occurs in the combustion chamber, the faulty combustion chamber can be accurately located, and the phenomenon that the faulty combustion chamber cannot be accurately located due to the migration of hot spots caused by the rotation of turbine blades can be avoided. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 It is a schematic diagram of the system structure and workflow of the present invention.

[0040] Figure 2 It is a schematic diagram of an embodiment of the present invention.

[0041] Description of reference numerals:

[0042] 1. Operating condition parameter module; 2. Initial state data acquisition module; 3. TDLAS combustion state parameter monitoring module; 4. Combustion criterion storage module; 5. Combustion state diagnosis module. DETAILED DESCRIPTION

[0043] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present disclosure and to be able to fully convey the scope of the present disclosure to those skilled in the art. It should be noted that, in the absence of conflict, the embodiments of the present invention and the features described in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0044] The application fields of the present invention are as follows Figure 1 A combustion diagnostic device suitable for a gas turbine is shown in FIG. Figure 1 As shown, the present invention provides a combustion diagnosis device suitable for a gas turbine, comprising an operating condition parameter module 1, an initial state data acquisition module 2, a TDLAS combustion state parameter monitoring module 3, a combustion criterion storage module 4 and a combustion state diagnosis module 5.

[0045] When working, the operating condition parameter module 1 obtains the gas turbine operating condition from the existing control system of the gas turbine, and outputs the operating condition parameters to the combustion diagnosis criterion storage module 4 and the combustion diagnosis module 5. The initial state acquisition module 2 obtains the compressor exhaust temperature and exhaust pressure from the existing measurement system of the gas turbine, and uses them as the initial state parameters T of the combustion chamber. C,0 and P C,0 The air humidity is obtained by the air humidity measuring device in the gas turbine inlet and converted into the initial H2O concentration D in the combustion chamber. H2O,0 , and T C,0 , P C,0 and D H2O,0 The information is provided to the combustion state diagnosis module 5. The TDLAS combustion state parameter monitoring module 3 couples two narrow-band laser signals that can be absorbed by H2O into a beam of parallel light. The parallel light to be coupled passes through the flow field to be measured in the gas turbine combustion chamber and is received by the TDLAS combustion state monitoring module. It is converted into the real-time temperature T of the combustion chamber through calculation and analysis. C,t , combustion chamber pressure pulsation frequency P HC,t , pressure pulsation amplitude P at different frequencies AC,t And the H2O component concentration D H2O,tThe combustion condition parameters real-time information is provided to the combustion condition diagnosis module 5. The combustion criterion storage module 4 pre-stores the combustion temperature warning value and alarm value of the gas turbine combustion chamber outlet plane under different working conditions, the inherent acoustic frequency of the combustion chamber components, the warning value of the combustion chamber pressure pulsation frequency and amplitude under different working conditions, the trip value and other information, and selects the warning value T of the combustion temperature of the combustion chamber under the corresponding working condition according to the operating condition parameters input by the operating condition parameter module 1. C,10 And alarm value T C,20 and the natural acoustic frequency P of the combustion chamber components HC,0 , the warning value P of pressure pulsation amplitude and frequency AC,10 and trip value P AC,20 Wait until combustion diagnosis module 5.

[0046] The combustion state diagnosis module 5 collects data and information provided by the operating condition parameter module 1, the initial state data acquisition module 2, the TDLAS combustion state parameter monitoring module 3, and the combustion criterion storage module 4, and sends combustion state information such as normal combustion temperature, high combustion temperature and over-temperature combustion temperature to the gas turbine control system by comparing and analyzing the initial temperature of the combustion chamber obtained by the initial state data acquisition module, the combustion chamber temperature provided by the TDLAS monitoring module and the combustion temperature reference value stored in the combustion criterion storage module; sends combustion chamber ignition success, ignition failure and other information to the gas turbine control system by comparing and analyzing the combustion chamber H2O provided by the TDLAS monitoring module and the H2O concentration stored in the combustion criterion storage module; and sends combustion state information such as stable combustion, unstable combustion warning and unstable combustion to the gas turbine control system by comparing and analyzing the combustion chamber pressure pulsation amplitude and frequency provided by the TDLAS monitoring module.

[0047] Preferably, the high-temperature combustion gas in the combustion chamber isolated by high-temperature resistant quartz glass can be used to establish a TDLAS combustion state monitoring module to provide an optical monitoring window, ensuring that the laser can smoothly pass through the flow field to be measured in the gas turbine combustion chamber without contacting the high-temperature combustion gas in the gas turbine combustion chamber, thereby realizing the monitoring of state parameters such as combustion temperature, pressure and H2O composition.

[0048] Preferably, the combustion criterion storage module 3 stores temperature reference information, H2O concentration reference information, pressure reference information, etc. of the gas turbine combustion chamber, and the stored temperature reference information of the combustion chamber is derived from the average value of combustion state parameters such as temperature, H2O concentration, pressure, etc. at the outlet plane of the transition section of the gas turbine combustion chamber.

[0049] Preferably, the combustion diagnosis module 5 diagnoses combustion state information such as whether the combustion temperature of the combustion chamber is normal, whether the combustion temperature is too high, and whether the combustion temperature is over-temperature through simple logical judgment, such as comparing the temperature reference value of the combustion chamber under different working conditions with the size of the real-time temperature of the combustion chamber provided by the TDLAS combustion temperature monitoring system; such as comparing and analyzing the concentration of H2O in the combustion chamber provided by the TDLAS monitoring module 2 and the H2O concentration stored in the combustion criterion storage module 3, diagnosing information such as successful ignition or failed ignition of the combustion chamber; such as comparing and analyzing the difference between the information such as the amplitude and frequency of the combustion chamber pressure pulsation provided by the TDLAS monitoring module and the combustion pressure pulsation reference information stored in the storage module 3, diagnosing combustion state information such as combustion stability, combustion instability warning, and combustion instability of the gas turbine combustion chamber; and sending the above diagnosis results to the gas turbine control system.

[0050] Preferably, a combustion diagnosis logic in a combustion diagnosis method applicable to a gas turbine is as follows:

[0051] If T Ct –T C0 ≥0 and D H2O,t –D H2O,0 >0, indicating that there is continuous flame in the combustion chamber, and the combustion diagnosis module outputs status words such as combustion chamber ignition success;

[0052] If D H2O,t –D H2O,0 ≤0, indicating that there is no continuous flame in the combustion chamber, and the combustion diagnosis module outputs status words such as combustion chamber ignition failure;

[0053] If T C,t -T C,0 >0 and T C,t –T C,10 <0, indicating that the combustion chamber temperature is normal, and the combustion diagnosis module issues a combustion chamber temperature normal status word;

[0054] If T C,t -T C,0 >0 and T C,t –T C,10 ≥0 and T C,t –T C,20 <0, indicating that the combustion chamber combustion temperature is high and close to the combustion chamber temperature upper limit, and the combustion diagnosis module issues a high combustion chamber temperature warning status word;

[0055] If T C,t -T C,0 >0 and T C,t –T C,20 ≥0, indicating that the combustion chamber temperature exceeds the safe operating range of the combustion chamber, and the combustion diagnosis module issues a combustion over-temperature alarm status word;

[0056] If |PHC,t -P HC,0 |<50Hz, indicating that the combustion chamber pressure pulsation frequency is close to the combustion chamber natural frequency, and the combustion chamber is very likely to resonate. The combustion diagnosis system issues a combustion chamber resonance status word, and the engine trips;

[0057] If |P HC,t -P HC,0 |≥50Hz, and P AC,t -P AC,10 <0, indicating that the combustion chamber pressure pulsation frequency and pressure pulsation amplitude are both within the combustion safety and stability range, the combustion chamber combustion is stable, and the combustion diagnosis module outputs the combustion stability state word;

[0058] If |P HC,t -P HC,0 |≥50Hz, and P AC,t -P AC,10 ≥0 and P AC,t -P AC,20 <0, indicating that the combustion chamber pressure pulsation frequency is within the safe range, but the combustion chamber pressure pulsation amplitude is close to the safety upper limit, and the combustion diagnosis module issues a combustion pressure pulsation warning status word;

[0059] If |P HC,t -P HC,0 |≥50Hz, and P AC,t -P AC,20 ≥0, indicating that the combustion chamber pressure pulsation frequency is within the safe range, but the combustion chamber pressure pulsation amplitude exceeds the combustion chamber pressure pulsation amplitude safety upper limit, and the combustion diagnosis module issues a combustion pressure pulsation high alarm status word.

[0060] Example

[0061] like Figure 2 As shown, when the gas turbine combustion chamber is working, the operating condition parameter module 1 obtains the gas turbine operating condition from the existing control system of the gas turbine, and outputs the operating condition parameters to the combustion diagnosis criterion storage module 4 and the combustion diagnosis module 5. The initial state acquisition module 2 obtains the compressor exhaust temperature and exhaust pressure from the existing measurement system of the gas turbine, and uses them as the initial state parameters T of the combustion chamber. C,0 and P C,0 The air humidity is obtained by the air humidity measuring device in the gas turbine inlet and converted into the initial H2O concentration D in the combustion chamber. H2O,0 , and T C,0 , P C,0 and D H2O,0The information is provided to the combustion state diagnosis module 5. The TDLAS combustion state parameter monitoring module 3 couples two narrow-band laser signals that can be absorbed by H2O into a beam of parallel light. The parallel light to be coupled passes through the flow field to be measured in the gas turbine combustion chamber and is received by the TDLAS combustion state monitoring module. It is converted into the real-time temperature T of the combustion chamber through calculation and analysis. C,t , combustion chamber pressure pulsation frequency P HC,t , pressure pulsation amplitude P at different frequencies AC,t And the H2O component concentration D H2O,t The combustion condition parameters real-time information is provided to the combustion condition diagnosis module 5. The combustion criterion storage module 4 pre-stores the combustion temperature warning value and alarm value of the gas turbine combustion chamber outlet plane under different working conditions, the inherent acoustic frequency of the combustion chamber components, the warning value of the combustion chamber pressure pulsation frequency and amplitude under different working conditions, the trip value and other information, and selects the warning value T of the combustion temperature of the combustion chamber under the corresponding working condition according to the operating condition parameters input by the operating condition parameter module 1. C,10 And alarm value T C,20 and the natural acoustic frequency P of the combustion chamber components HC,0 , the warning value P of pressure pulsation amplitude and frequency AC,10 and trip value P AC,20 Wait until combustion diagnosis module 5.

[0062] The combustion state diagnosis module 5 collects data and information provided by the operating condition parameter module 1, the initial state data acquisition module 2, the TDLAS combustion state parameter monitoring module 3, and the combustion criterion storage module 4, and sends combustion state information such as normal combustion temperature, high combustion temperature and over-temperature combustion temperature to the gas turbine control system by comparing and analyzing the initial temperature of the combustion chamber obtained by the initial state data acquisition module, the combustion chamber temperature provided by the TDLAS monitoring module and the combustion temperature reference value stored in the combustion criterion storage module; sends combustion chamber ignition success, ignition failure and other information to the gas turbine control system by comparing and analyzing the combustion chamber H2O provided by the TDLAS monitoring module and the H2O concentration stored in the combustion criterion storage module; and sends combustion state information such as stable combustion, unstable combustion warning and unstable combustion to the gas turbine control system by comparing and analyzing the combustion chamber pressure pulsation amplitude and frequency provided by the TDLAS monitoring module.

[0063] Preferably, the gas turbine combustion chamber uses high-temperature resistant quartz glass to isolate the high-temperature combustion gas; the high-temperature resistant quartz glass has a diameter of no more than 10 mm and a thickness of no less than 10 mm, and is arranged near the outlet plane of the transition section of the gas turbine combustion chamber, and its plane in contact with the high-temperature combustion gas is flush with the inner wall surface of the combustion chamber, does not affect the flow field organization inside the combustion chamber, and has little effect on the structural strength of the combustion chamber components; based on the high-temperature resistant quartz glass, a TDLAS combustion state monitoring module can be formed to provide an optical monitoring window, ensuring that the laser can smoothly pass through the flow field to be measured in the gas turbine combustion chamber without contacting the high-temperature combustion gas in the gas turbine combustion chamber, thereby realizing the monitoring of state parameters such as combustion temperature, pressure and H2O component.

[0064] Preferably, the two lasers that can be emitted by the TDLAS combustion state monitoring module 3 and can be absorbed by H2O are both single-mode lasers with wavelengths between 1260nm and 1650nm, which are within the working band of the DFB diode laser for communication, and the spectral line intensity values ​​of the two lasers at 450℃ to 1800℃ are not much different.

[0065] Preferably, the combustion criterion storage module 4 stores the temperature reference value, H2O concentration reference value, pressure reference value, etc. of the gas turbine combustion chamber, and the stored combustion chamber temperature reference value is the average combustion temperature of the combustion chamber transition section outlet plane.

[0066] Preferably, the combustion diagnosis module 5 can diagnose the combustion ignition state, combustion temperature state and combustion stability state of the gas turbine combustion chamber through simple combustion diagnosis logic, and can send combustion state information such as ignition success, ignition failure, normal combustion temperature, high combustion temperature warning, combustion over-temperature trip, combustion resonance, combustion stability, combustion pressure pulsation amplitude high warning, combustion pressure pulsation amplitude high alarm to the gas turbine control system.

[0067] Preferably, a combustion diagnosis logic in a combustion diagnosis method applicable to a gas turbine is as follows:

[0068] If T Ct –T C0 ≥0 and D H2O,t –D H2O,0 >0, indicating that there is continuous flame in the combustion chamber, and the combustion diagnosis module outputs status words such as combustion chamber ignition success;

[0069] If D H2O,t –D H2O,0 ≤0, indicating that there is no continuous flame in the combustion chamber, and the combustion diagnosis module outputs status words such as combustion chamber ignition failure;

[0070] If T C,t -T C,0 >0 and TC,t –T C,10 <0, indicating that the combustion chamber temperature is normal, and the combustion diagnosis module issues a combustion chamber temperature normal status word;

[0071] If T C,t -T C,0 >0 and T C,t –T C,10 ≥0 and T C,t –T C,20 <0, indicating that the combustion chamber combustion temperature is high and close to the combustion chamber temperature upper limit, and the combustion diagnosis module issues a high combustion chamber temperature warning status word;

[0072] If T C,t -T C,0 >0 and T C,t –T C,20 ≥0, indicating that the combustion chamber temperature exceeds the safe operating range of the combustion chamber, and the combustion diagnosis module issues a combustion over-temperature alarm status word;

[0073] If |P HC,t -P HC,0 |<50Hz, indicating that the combustion chamber pressure pulsation frequency is close to the combustion chamber natural frequency, and the combustion chamber is very likely to resonate. The combustion diagnosis system issues a combustion chamber resonance status word, and the engine trips;

[0074] If |P HC,t -P HC,0 |≥50Hz, and P AC,t -P AC,10 <0, indicating that the combustion chamber pressure pulsation frequency and pressure pulsation amplitude are both within the combustion safety and stability range, the combustion chamber combustion is stable, and the combustion diagnosis module outputs the combustion stability state word;

[0075] If |P HC,t -P HC,0 |≥50Hz, and P AC,t -P AC,10 ≥0 and P AC,t -P AC,20 <0, indicating that the combustion chamber pressure pulsation frequency is within the safe range, but the combustion chamber pressure pulsation amplitude is close to the safety upper limit, and the combustion diagnosis module issues a combustion pressure pulsation warning status word;

[0076] If |P HC,t -P HC,0 |≥50Hz, and P AC,t -P AC,20 ≥0, indicating that the combustion chamber pressure pulsation frequency is within the safe range, but the combustion chamber pressure pulsation amplitude exceeds the combustion chamber pressure pulsation amplitude safety upper limit, and the combustion diagnosis module issues a combustion pressure pulsation high alarm status word.

[0077] Although the present invention has been described in detail above with general descriptions and specific embodiments, it is obvious to those skilled in the art that some modifications or improvements may be made thereto based on the present invention. Therefore, these modifications or improvements made without departing from the spirit of the present invention all fall within the scope of protection claimed by the present invention.

Claims

1. A combustion diagnosis method applicable to a gas turbine, characterized in that: The following steps are involved: Step 1: Obtain the gas turbine IGV angle, fuel flow and temperature, and gas turbine load to determine the gas turbine operating conditions; Step 2: According to the operating condition of the gas turbine, a combustion state diagnosis criterion of the gas turbine combustion chamber is obtained, including temperature reference information, H2O concentration reference information and pressure reference information of the gas turbine combustion chamber under the operating condition; The temperature reference information of the gas turbine combustion chamber described in the combustion state diagnosis criterion of the gas turbine combustion chamber at least includes an array T of normal ranges of the combustion temperature of the combustion chamber under different working conditions. Z , warning value T C,10 And the alarm value T C,20 The stored combustion chamber pressure reference information includes the natural acoustic frequency P of the combustion chamber components. HC,0 , the warning value P of the combustion chamber pressure pulsation amplitude under different working conditions AC,10 and trip value P AC,20 , and the combustion state diagnosis criteria under different working conditions of the gas turbine combustion chamber are stored in the combustion criterion diagnosis module; Step 3: Obtain atmospheric humidity and convert it into initial H2O concentration of the gas turbine combustion chamber; obtain the compressor exhaust temperature and exhaust pressure and use them as the initial temperature and pressure of the gas turbine combustion chamber; Step 4, using the TDLAS combustion monitoring module to obtain the combustion temperature, combustion chamber pressure and combustion state parameters of the combustion chamber H2O concentration, and converting the combustion pressure into pressure pulsation frequency and amplitude through fast Fourier transform; the two lasers that can be absorbed by H2O emitted by the TDLAS combustion monitoring module are single-mode lasers with wavelengths between 1260nm and 1650nm, and the spectral line intensities of the two lasers at 450℃ to 1800℃ are not much different; the TDLAS combustion monitoring module is used to monitor the combustion flow field parameters near the outlet of the transition section of the combustion chamber, and it converts the light intensity change information of the laser absorption spectrum into the temperature value T of the flow field to be measured in the combustion chamber according to the single-value conversion formula between light intensity and temperature. C,t ; By analyzing the one-to-one correspondence between the broadening of the absorption spectrum signal and the pressure, it is converted into the pressure value P of the flow field to be measured in the combustion chamber C,t , and then perform FFT conversion on the flow field pressure to obtain the pressure pulsation frequency P of the flow field to be measured in the combustion chamber HC,t and the corresponding amplitude P AC,t Analyze the line type and second harmonic peak information of the laser absorption spectrum signal, and obtain the H2O concentration D of the flow field to be measured in the combustion chamber based on the corresponding relationship between the component concentration and the second harmonic peak, combined with the combustion temperature and combustion pressure information. H2O,t ; Step 5: Compare and analyze the initial H2O concentration of the combustion chamber with the real-time H2O concentration of the combustion chamber, compare and analyze the initial temperature of the combustion chamber with the real-time combustion temperature of the combustion chamber, diagnose whether there is flame in the combustion chamber according to the combustion diagnosis logic, diagnose the ignition state of the combustion chamber, and send out ignition success and combustion chamber no flame ignition failure signals according to the diagnosis results; by comparing and analyzing the H2O concentration D of the combustion chamber provided by the TDLAS monitoring module H2O,t The H2O concentration D stored in the combustion chamber initial state acquisition module H2O,0 , and compare and analyze the combustion chamber temperature T provided by the TDLAS monitoring module C,t The initial temperature T of the combustion chamber stored in the combustion initial state parameter acquisition module C,0 , diagnose the combustion chamber ignition status according to the combustion diagnosis logic and send the combustion chamber ignition success and ignition failure information to the gas turbine control system; Step 6: Compare and analyze the initial temperature of the combustion chamber, the real-time temperature of the combustion chamber, and the combustion temperature reference information in the combustion diagnosis criterion, diagnose the combustion chamber temperature according to the combustion diagnosis logic, and issue a normal combustion temperature, a high combustion temperature warning, and a combustion temperature over-temperature trip according to the diagnosis result; Step 7: Compare and analyze the initial pressure of the combustion chamber, the obtained combustion chamber pressure pulsation information, and the combustion pressure reference information in the combustion diagnosis criterion, diagnose the combustion stability according to the combustion diagnosis logic, and issue combustion stability, combustion pressure pulsation high warning and combustion instability trip signal according to the diagnosis result; The combustion diagnosis logic in the combustion diagnosis method applicable to gas turbines is as follows: If T C,t –T C,0 ≥0 and D H2O,t –D H2O,0 >0, indicating that there is continuous flame in the combustion chamber, and the combustion diagnosis module outputs the combustion chamber ignition success and continuous flame status word; If D H2O,t –D H2O,0 ≤0, indicating that there is no continuous flame in the combustion chamber, and the combustion diagnosis module outputs the combustion chamber ignition failure and the state word of no continuous flame; If T C,t -T C,0 >0 and T C,t –T C,10 <0, indicating that the combustion chamber temperature is normal, and the combustion diagnosis module issues a combustion chamber temperature normal status word; If T C,t -T C,0 >0 and T C,t –T C,10 ≥0 and T C,t –T C,20 <0, indicating that the combustion chamber combustion temperature is high and close to the combustion chamber temperature upper limit, and the combustion diagnosis module issues a high combustion chamber temperature warning status word; If T C,t -T C,0 >0 and T C,t –T C,20 ≥0, indicating that the combustion chamber temperature exceeds the safe operating range of the combustion chamber, and the combustion diagnosis module issues a combustion over-temperature alarm status word; If |P HC,t -P HC,0 |<50Hz, indicating that the combustion chamber pressure pulsation frequency is close to the combustion chamber natural frequency, and the combustion chamber is very likely to resonate. The combustion diagnosis system issues a combustion chamber resonance status word, and the engine trips; If |P HC,t -P HC,0 |≥50Hz, and P AC,t -P AC,10 <0, indicating that the combustion chamber pressure pulsation frequency and pressure pulsation amplitude are both within the combustion safety and stability range, the combustion chamber combustion is stable, and the combustion diagnosis module outputs the combustion stability state word; If |P HC,t -P HC,0 |≥50Hz, and P AC,t -P AC,10 ≥0 and P AC,t -P AC,20 <0, indicating that the combustion chamber pressure pulsation frequency is within the safe range, but the combustion chamber pressure pulsation amplitude is close to the safety upper limit, and the combustion diagnosis module issues a combustion pressure pulsation warning status word; If |P HC,t -P HC,0 |≥50Hz, and P AC,t -P AC,20 ≥0, indicating that the combustion chamber pressure pulsation frequency is within the safe range, but the combustion chamber pressure pulsation amplitude exceeds the combustion chamber pressure pulsation amplitude safety upper limit, and the combustion diagnosis module issues a combustion pressure pulsation high alarm status word.

2. A combustion diagnosis method suitable for a gas turbine according to claim 1, characterized in that: The IGV angle, fuel flow and temperature, and engine load parameters in step 1 can be obtained from the gas turbine control system and stored in the operating condition parameter storage module.

3. A combustion diagnosis method suitable for a gas turbine according to claim 1, characterized in that: In step 3, the existing atmospheric humidity monitoring equipment of the gas turbine is used to obtain and convert it into the initial H2O concentration D in the gas turbine combustion chamber. H2O,0 ; Use the existing compressor exhaust temperature and exhaust pressure equipment of the gas turbine to obtain and use it as the initial temperature T of the gas turbine combustion chamber C,0 and initial pressure P C,0 , and the data is stored in the combustion chamber initial state acquisition module.

4. A combustion diagnosis method suitable for a gas turbine according to claim 1, characterized in that: In step 6, the initial temperature T of the combustion chamber obtained by comparing and analyzing the initial state acquisition module C,0 , the combustion chamber temperature T provided by the TDLAS monitoring module C,t The early warning value T of the combustion chamber combustion temperature under different working conditions stored in the combustion diagnosis criterion storage module C,10 And the alarm value T C,20 , diagnose the combustion chamber temperature status according to the combustion diagnosis logic, and send the combustion status information of normal combustion temperature, high combustion temperature and over-temperature combustion temperature to the gas turbine control system.

5. A combustion diagnosis method applicable to a gas turbine according to claim 1, characterized in that: In step 7, the combustion chamber pressure pulsation frequency P provided by the TDLAS monitoring module is compared and analyzed. HC,t and the corresponding amplitude P AC,t The combustion chamber pressure reference information stored in the combustion diagnosis criterion storage module includes the natural acoustic frequency P of the combustion chamber components under different working conditions. HC,0 , the warning value P of the pressure pulsation amplitude and frequency AC,10 and trip value P AC,20 , diagnose the combustion stability of the combustion chamber according to the combustion diagnosis logic, and send combustion pressure pulsation stability, combustion instability warning and combustion instability trip combustion status information to the gas turbine control system.

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