# US 10,371,002 B2 · Control system for a gas turbine engine > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,371,002 B2 - Document ID: US10371002B2 - Status: Granted - Kind: B2 - Application number: 15/181,461 - Filed: 2016-06-14 - Published: 2017-12-14 - Granted: 2019-08-06 - Earliest claimed: 2016-06-14 - Assignees: General Electric Company - Applicants: General Electric Company - Inventors: Nicholas Adam Descamps; David Alexander Hiett; John Thomas Lammers; Robert Charles Hon; Thomas Charles Swager - Web page: https://patentgrep.com/patent/US10371002B2 ## CPC - F01D 19/00: Starting of machines or engines; Regulating, controlling, or safety means in connection therewith (warming-up before starting F01D25/10; turning or inching gear F01D25/34) - F01D 21/06: Shutting-down - F02C 7/262: Restarting after flame-out - 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 9/46: Emergency fuel control - F05D 2220/32: in gas turbines - F05D 2260/80: Diagnostics - F05D 2260/85: Starting - F05D 2270/092: in particular blow-out and relight - F05D 2270/304: Spool rotational speed - F05D 2270/334: Vibration measurements - Y02T 50/60: Efficient propulsion technologies, e.g. for aircraft - F01D: NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES (machines or engines for liquids F03; non-positive displacement pumps F04D) - 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) - F05D: INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract Systems and methods for shutting down a gas turbine engine in response to a severe mechanical failure include determining a rate of change of one or more process conditions. If the rate of change of the one or more process conditions exceeds a respective predetermined failure threshold, a potential severe mechanical failure of the gas turbine engine may be determined. Steps may be taken to confirm the potential severe mechanical failure of the gas turbine engine. In response, an engine restart is prevented. ## Claims ### Claim 1 A method for preventing a gas turbine engine restart in response to a severe mechanical failure, the method comprising: determining a first process condition, or a rate of change of the first process condition, exceeds a first failure threshold, the first failure threshold indicative of a severe mechanical failure of the gas turbine engine; determining a potential severe mechanical failure of the gas turbine engine based at least in part on the determined process condition, or the determined rate of change of the first process condition, exceeding the first failure threshold; confirming the potential severe mechanical failure of the gas turbine engine by determining both an accommodation time period following the determined potential severe mechanical failure has not elapsed and determining the gas turbine engine is operating in sub-idle conditions within the accommodation time period, wherein determining the gas turbine engine is operating in sub-idle conditions within the accommodation time period comprises determining the gas turbine engine has reached sub-idle conditions within the accommodation time period; and preventing an engine restart based at least in part on determining the gas turbine engine is operating in sub-idle conditions. ### Claim 2 (depends on 1) The method of claim 1, wherein confirming the potential severe mechanical failure of the gas turbine engine further comprises determining the gas turbine engine is operating within a susceptibility window. ### Claim 3 (depends on 2) The method of claim 2, wherein determining the gas turbine engine is operating within the susceptibility window comprises determining the gas turbine engine is operating below a predetermined fire threat flight altitude. ### Claim 4 (depends on 1) The method of claim 1, wherein the first process condition is chosen from a group comprising: a low pressure spool speed, a high pressure spool speed, a compressor discharge pressure, and a component vibration. ### Claim 5 (depends on 1) The method of claim 1, wherein determining the first process condition, or the rate of change of the first process condition, exceeds the first failure threshold comprises determining the rate of change of the first process condition exceeds the first failure threshold, and wherein the first process condition is chosen from a group comprising: a low pressure spool speed, a high pressure spool speed, and a compressor discharge pressure. ### Claim 6 (depends on 1) The method of claim 1, further comprising: determining a second process condition and a third process condition; determining a rate of change of the second process condition and a rate of change of the third process condition, wherein confirming the potential severe mechanical failure comprises determining that at least one of the rate of change of the second process condition exceeds a second failure threshold or the rate of change of the third process condition exceeds a third failure threshold. ### Claim 7 (depends on 6) The method of claim 6, wherein the first process condition, the second process condition, and the third process condition are chosen from the group comprising: a low pressure spool speed, a high pressure spool speed, and a compressor discharge pressure. ### Claim 8 (depends on 6) The method of claim 6, wherein the third process condition is a compressor pressure, wherein determining the rate of change of the compressor pressure exceeds the third failure threshold further comprises determining a present value of the compressor pressure remains below a determined value. ### Claim 9 (depends on 1) The method of claim 1, wherein preventing the engine restart comprises at least one of closing one or more fuel metering valves of a fuel system of the gas turbine engine or disabling an ignition system. ### Claim 10 (depends on 1) The method of claim 1, wherein the severe mechanical failure is at least one of a fan blade out event or a shaft sheer event. ### Claim 11 (depends on 1) The method of claim 1, wherein preventing the engine restart comprises preventing the engine restart in response to determining the potential severe mechanical failure of the gas turbine engine and confirming the potential severe mechanical failure of the gas turbine engine. ### Claim 12 A method for preventing a gas turbine engine restart in response to a severe mechanical failure, the method comprising: determining a rate of change of a first process condition, a rate of change of a second process condition, and a third process condition; determining a potential severe mechanical failure of the gas turbine engine based on at least two of the following: the rate of change of the first process condition exceeding a first failure threshold, the rate of change of the second process condition exceeding a second failure threshold, or the third process condition, or a rate of change of the third process condition, exceeding a third failure threshold; confirming the potential severe mechanical failure of the gas turbine engine, wherein confirming the potential severe mechanical failure of the gas turbine engine comprises determining both an accommodation time period following the determined potential severe mechanical failure has not elapsed and determining the gas turbine engine is operating in sub-idle conditions within the accommodation time period, wherein determining the gas turbine engine is operating in sub-idle conditions within the accommodation time period comprises determining the gas turbine engine has reached sub-idle conditions within the accommodation time period; and preventing an engine restart based at least in part on determining the gas turbine engine is operating in sub-idle conditions. ### Claim 13 (depends on 12) The method of claim 12, wherein determining the potential severe mechanical failure of the gas turbine engine is based at least in part on the rate of change of the third process condition, wherein the third process condition is a compressor pressure, and wherein determining the potential severe mechanical failure of the gas turbine engine is further based on determining a present compressor pressure remains below a determined pressure. ### Claim 14 (depends on 12) The method of claim 12, wherein determining the potential severe mechanical failure of the gas turbine engine is based at least in part on the third process condition, wherein the third process condition is a component vibration. ### Claim 15 (depends on 12) The method of claim 12, wherein the first process condition is a low pressure spool speed, wherein the second process condition is a high pressure spool speed, and wherein the third process condition is a compressor discharge pressure. ### Claim 16 A control system for preventing a gas turbine engine restart in response to a severe mechanical failure, the system comprising one or more processors and one or more memory devices included with the gas turbine engine, the one or more memory devices storing instructions that when executed by the one or more processors cause the one or more processors to perform operations, the operations comprising: determining a rate of change of a first process condition exceeds a first failure threshold, the first failure threshold indicative of a severe mechanical failure of the gas turbine engine; determining a potential severe mechanical failure of the gas turbine engine based at least in part on the determined rate of change of the first process condition exceeding the first failure threshold; confirming the potential severe mechanical failure of the gas turbine engine by determining both an accommodation time period following the determined potential severe mechanical failure has not elapsed and determining the gas turbine engine is operating in sub-idle conditions within the accommodation time period, wherein determining the gas turbine engine is operating in sub-idle conditions within the accommodation time period comprises determining the gas turbine engine has reached sub-idle conditions within the accommodation time period; and preventing an engine restart based at least in part on determining the gas turbine engine is operating in sub-idle conditions. ### Claim 17 (depends on 16) The control system of claim 16, wherein confirming the potential severe mechanical failure of the gas turbine engine further comprises determining the gas turbine engine is operating below a predetermined fire threat flight altitude.