# US 2014/0196461 A1 · Detecting flashback by monitoring engine-dynamic spikes > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0196461 A1 - Document ID: US20140196461A1 - Status: Published application - Kind: A1 - Application number: 13/742,401 - Filed: 2013-01-16 - Published: 2014-07-17 - Earliest claimed: 2013-01-16 - Assignees: ALSTOM Technology Ltd - Applicants: Alstom Technology Ltd. - Inventors: SUMIT SONI; DONALD GAUTHIER; HANY RIZKALLA; KHALID OUMEJJOUD; PETER STUTTAFORD - Web page: https://patentgrep.com/patent/US20140196461A1 ## CPC - F02C 9/00: Controlling gas-turbine plants; Controlling fuel supply in air- breathing jet-propulsion plants (controlling air intakes F02C7/057; controlling turbines F01D; controlling compressors F04D27/00; controlling in general G05) - F02C 9/28: Regulating systems responsive to plant or ambient parameters, e.g. temperature, pressure, rotor speed (F02C9/30 - F02C9/38, F02C9/44 take precedence) - F23D 14/82: Preventing flashback or blowback - F23N 5/16: using noise-sensitive detectors - F23R 3/34: Feeding into different combustion zones - F23D 2209/10: Flame flashback - F23N 2231/28: preventing flash-back or blow-back - F23R 2900/00013: Reducing thermo-acoustic vibrations by active means - F02C: GAS-TURBINE PLANTS; AIR INTAKES FOR JET-PROPULSION PLANTS; CONTROLLING FUEL SUPPLY IN AIR-BREATHING JET-PROPULSION PLANTS (construction of turbines F01D; jet-propulsion plants F02K; construction of compressors or fans F04; generating combustion products of high pressure or high velocity F23R; using gas turbines in compression refrigeration plants F25B11/00) - F23D: BURNERS - F23N: REGULATING OR CONTROLLING COMBUSTION (control devices specially adapted for combustion apparatus in which combustion takes place in a fluidised bed of fuel or other particles F23C10/28; condition responsive controls for regulating combustion in domestic stoves with open fires for solid fuel F24B1/187) - F23R: GENERATING COMBUSTION PRODUCTS OF HIGH PRESSURE OR HIGH VELOCITY, e.g. GAS-TURBINE COMBUSTION CHAMBERS (fluidised bed combustion apparatus specially adapted for operation at superatmospheric pressures F23C10/16) ## Abstract A tuning process is provided for dynamically tuning a gas-turbine (GT) engine to correct for flashback events without directly measuring occurrences of the flashback events at the GT engine. Initially, readings are taken that measure low-frequency dynamics at the GT engine. A determination of whether flashback criteria are met by an instantaneous signal that quantifies a detected spike within the measured low-frequency dynamics is carried out, where the flashback criteria include the following: identifying the spike overcomes a multiple of an average of the low-frequency dynamics measured over a predefined period of time; and identifying the spike overcomes a preestablished minimum amplitude. Upon the spike meeting the flashback criteria, a count is added to a running record of spikes, which is compared to an alarm limit. If the alarm limit is triggered, action(s) are invoked to address the flashback events, such as adjusting fuel-flow splits of the GT engine. ## Claims ### Claim 1 A computerized method, implemented by a processing unit, for automatically tuning a combustor of a gas turbine (GT) engine to address the occurrences of flashback events, the method comprising: monitoring one or more low-frequency dynamics within the GT engine when tuning a control system for managing operation of the GT engine; detecting a spike in the one or more monitored low-frequency dynamics; determining whether an amplitude measured from the spike satisfies at least one flashback criterion; when the spike's measured amplitude satisfies the at least one flashback criterion, causing a flashback-addressing action to commence, wherein the flashback-addressing action serves to influence the occurrences of flashback events within the GT engine; and otherwise, refraining from causing the flashback-addressing action. ### Claim 2 (depends on 1) The computerized method of claim 1, further comprising, upon determining that the spike's measured amplitude satisfies the at least one flashback criterion, adding a count to a running record of spikes detected from the GT engine. ### Claim 3 (depends on 2) The computerized method of claim 2, further comprising determining whether the running record of spikes triggers an alarm limit. ### Claim 4 (depends on 3) The computerized method of claim 3, wherein determining whether the running record of spikes triggers an alarm limit comprises identifying that a number of spikes, which satisfy the at least one flashback criterion, detected within a predefined time interval surpasses a threshold number. ### Claim 5 (depends on 3) The computerized method of claim 3, further comprising, upon determining that the running record of spikes triggers an alarm limit, causing the flashback-addressing action to commence. ### Claim 6 (depends on 5) The computerized method of claim 5, wherein causing the flashback-addressing action to commence comprises adjusting one or more fuel-flow splits while maintaining a total fuel flow to the GT engine substantially constant. ### Claim 7 (depends on 1) The computerized method of claim 1, wherein monitoring one or more low-frequency dynamics within the GT engine comprises measuring low-frequency dynamics. ### Claim 8 (depends on 7) The computerized method of claim 7, wherein the low-frequency dynamics include lean blowout (LBO) of the GT engine. ### Claim 9 (depends on 7) The computerized method of claim 7, further comprising calculating an average of the one or more low-frequency dynamics over a predefined period of time. ### Claim 10 (depends on 9) The computerized method of claim 9, wherein determining whether an amplitude measured from the spike satisfies at least one flashback criterion comprises determining whether the spike's measured amplitude overcomes a first predetermined value, wherein the first predetermined value represents a multiple of the calculated average of the one or more low-frequency dynamics. ### Claim 11 (depends on 10) The computerized method of claim 10, wherein determining whether an amplitude measured from the spike satisfies at least one flashback criterion comprises determining whether the spike's measured amplitude overcomes a second predetermined value, wherein the second predetermined value represents a preestablished minimum amplitude. ### Claim 12 (depends on 11) The computerized method of claim 11, further comprising adding a count to a running record of spikes detected from the GT engine upon determining that the spike's measured amplitude overcomes the first and second predetermined values. ### Claim 13 A computer system for auto-tuning a gas turbine (GT) engine using engine dynamics to adjust for flashback events, the computer system comprising a processor coupled to a computer storage medium, the computer storage medium having stored thereon a plurality of computer software components executable by the processor, the computer software components comprising: an acquisition component that measures an instantaneous signal of low-frequency dynamics while monitoring the engine dynamics for the GT engine; a processing component that performs an analysis to determine whether the instantaneous signal qualifies as a spike that satisfies one or more flashback criteria, wherein performing the analysis comprises: (a) calculating an average of the measured low-frequency dynamics over a predefined period of time; (b) determining whether the instantaneous signal overcomes a first predetermined value of the one or more flashback criteria, wherein the first predetermined value represents a multiple of the calculated average; and (c) determining whether the instantaneous signal overcomes a second predetermined value of the one or more flashback criteria, wherein the second predetermined value represents preestablished minimum amplitude of the instantaneous signal; and an adjustment component that, upon receiving an indication that the instantaneous signal satisfies one or more flashback criteria, adjusts one or more fuel-flow splits while maintaining total fuel flow to the GT engine substantially constant. ### Claim 14 (depends on 13) The computer system of claim 13, wherein performing the analysis at the processing component further comprises: recognizing that the instantaneous signal overcomes the first and the second predetermined value; and adding a count to a running record of spikes detected from the GT engine. ### Claim 15 (depends on 14) The computer system of claim 14, wherein performing the analysis at the processing component further comprises upon adding the count to the running record of spikes to generate an updated running record, determining whether the updated running record triggers an alarm limit. ### Claim 16 (depends on 15) The computer system of claim 15, wherein, when the processing component determines that the alarm limit is triggered, sending the indication that the instantaneous signal satisfies the one or more flashback criteria to the adjustment component. ### Claim 17 (depends on 15) The computer system of claim 15, wherein, when the processing component determines that the alarm limit is not triggered, sending the indication to the adjustment component that indicates the fuel-flow splits are to remain unchanged. ### Claim 18 (depends on 13) The computer system of claim 13, wherein performing the analysis at the processing component further comprises: recognizing that the instantaneous signal overcomes either the first predetermined value or the second predetermined value; and adding a count to a running record of spikes detected from the GT engine. ### Claim 19 (depends on 13) The computer system of claim 13, wherein determining whether the instantaneous signal overcomes a first predetermined value of the one or more flashback criteria comprises identifying that the instantaneous signal overcomes a value that is four times the calculated average. ### Claim 20 One or more computer-readable media that, when invoked by computer-executable instructions, perform a method that adjusts one or more fuel-flow splits of a gas-turbine (GT) engine upon detecting the occurrence of flashback events, the method comprising: monitoring dynamics of the GT engine during an automated tuning procedure, wherein monitoring comprises: (a) measuring an instantaneous signal of lean blowout (LBO); and (b) averaging the measured LBO over a predefined period of time; determining whether a spike, as indicated by the instantaneous signal of the measured LBO, satisfies one or more flashback criteria, wherein determining comprises: (a) determining whether the spike overcomes a first predetermined value of the one or more flashback criteria, wherein the first predetermined value represents a multiple of the averaged LBO; or (b) determining whether the spike overcomes a second predetermined value of the one or more flashback criteria, wherein the second predetermined value represents preestablished minimum amplitude of the instantaneous signal; upon recognizing that the spike overcomes either the first predetermined value or the second predetermined value, generating an updated running record by adding a count to a running record of spikes detected from the GT engine; determining whether the updated running record overcomes an alarm limit; incident to determining that the updated running record overcomes the alarm limit, adjusting the one or more fuel-flow splits while maintaining total fuel flow to the GT engine substantially constant; and incident to determining that the updated running record fails to overcome the alarm limit, providing an indication that the fuel-flow splits are to remain unchanged.