Abstract: A method for safe gas turbine startup is disclosed. The method comprises a first step wherein a fuel metering valve (33) arranged along a fuel delivery line is tested for possible leakages. If the leakage test is successfully passed, a subsequent turbine startup step can be performed. Further disclosed is a gas turbine engine (3) comprising a fuel supply system (20) comprised of a fuel delivery line (21) and a valve arrangement (23) positioned along said fuel delivery line (21). The valve arrangement (23) further comprises sequentially arranged shut off valves (25, 29, 31) and a fuel metering valve (33), positioned downstream of the shut off valves (25, 29, 31). A pressure measuring arrangement (43, 45, 47) is further provided, adapted to measure fuel pressure in at least one portion of the fuel delivery line (21) upstream of the fuel metering valve (33).

Abstract: A method for safe gas turbine startup is disclosed. The method comprises a first step wherein a fuel metering valve (33) arranged along a fuel delivery line is tested for possible leakages. If the leakage test is successfully passed, a subsequent turbine startup step can be performed. Further disclosed is a gas turbine engine (3) comprising a fuel supply system (20) comprised of a fuel delivery line (21) and a valve arrangement (23) positioned along said fuel delivery line (21). The valve arrangement (23) further comprises sequentially arranged shut off valves (25, 29, 31) and a fuel metering valve (33), positioned downstream of the shut off valves (25, 29, 31). A pressure measuring arrangement (43, 45, 47) is further provided, adapted to measure fuel pressure in at least one portion of the fuel delivery line (21) upstream of the fuel metering valve (33).

Abstract: A method of starting a gas turbine and related apparatus, the method including keeping a main fuel line in a sealed state while allowing fuel to flow from a fuel source to at least one nozzle of a nozzle array via an auxiliary fuel line; firing a gas turbine while keeping the main fuel line in the sealed state; and after combustion has started: opening the main fuel line to commence a flow of fuel from the fuel source to the at least one nozzle of the nozzle array via the main fuel line, sealing the auxiliary fuel line, and after the auxiliary fuel line is sealed, increasing the flow of fuel from the fuel source to the at least one nozzle of the nozzle array via the main fuel line.

Abstract: Gas turbine, software and method for controlling an operating point of the gas turbine that includes a compressor, a combustor and at least a turbine is provided. The method includes determining a turbine exhaust pressure at an exhaust of the turbine; measuring a compressor pressure discharge at the compressor; determining a turbine pressure ratio based on the turbine exhaust pressure and the compressor pressure discharge; calculating an exhaust temperature at the exhaust of the turbine as a function of the turbine pressure ratio; identifying a reference exhaust temperature curve in a plane defined by the exhaust temperature and the turbine pressure ratio; and controlling the gas turbine to maintain the operating point on the reference exhaust temperature curve.

Abstract: A gas turbine, computer software and a method for controlling an operating point of the gas turbine that includes a compressor, a combustor and at least a turbine is provided. The method comprises: determining an exhaust pressure at an exhaust of the turbine; measuring a compressor pressure discharge at the compressor; determining a turbine pressure ratio based on the exhaust pressure and the compressor pressure discharge; calculating a primary to lean-lean mode transfer threshold reference curve as a function of the turbine pressure ratio, where the primary to lean-lean mode transfer threshold curve includes points at which an operation of the gas turbine is changed between a primary mode to a lean-lean mode; and controlling the gas turbine to change between the primary mode and the lean-lean mode.

Abstract: Gas turbine, computer readable medium, and method for controlling an operating point of the gas turbine that includes a compressor, a combustor and a turbine is provided. The method includes determining a turbine pressure ratio, calculating a primary to lean-lean mode transfer threshold reference curve as a function of the turbine pressure ratio, determining at a first time when an exhaust temperature associated with the operating point is higher than an exhaust temperature of the primary to lean-lean mode transfer threshold reference curve for the same turbine pressure ratio, and changing, after a predetermined time after the first time, a split fuel quantity from a first value to a second value if the exhaust temperature associated with the operating point remains higher than the exhaust temperature of the primary to lean-lean mode transfer threshold reference curve.

Abstract: Gas turbine and method for controlling an operating point of the gas turbine that includes a compressor, a combustor and at least a turbine. The method includes calculating an exhaust temperature reference curve of the turbine as a function of a turbine pressure ratio; determining whether condition IGVmin+?IGV1?IGVset point?IGVmax+?IGV2, and condition ttx?ttxh+?ttx3, are true; and changing, if both conditions are true, a split fuel quantity from a first value to a second value or otherwise maintaining the first value, the first value characterizing a lean-lean steady state mode and the second value characterizing a premixed secondary mode of a premixed mode.

Abstract: A gas turbine, computer software and a method for controlling an operating point of the gas turbine that includes a compressor, a combustor and at least a turbine is provided. The method comprises: determining an exhaust pressure at an exhaust of the turbine; measuring a compressor pressure discharge at the compressor; determining a turbine pressure ratio based on the exhaust pressure and the compressor pressure discharge; calculating a primary to lean-lean mode transfer threshold reference curve as a function of the turbine pressure ratio, where the primary to lean-lean mode transfer threshold curve includes points at which an operation of the gas turbine is changed between a primary mode to a lean-lean mode; and controlling the gas turbine to change between the primary mode and the lean-lean mode.

Abstract: A method is described for the start-up of a gas turbine comprising the phases of effecting a preliminary purging cycle of the discharge duct (28) of the turbine (20), establishing a predetermined minimum value (FSR1) for the flow of gaseous fuel entering the combustor (14) for a period of time which is adequate for effecting a first attempt at ignition and effecting a first attempt at ignition, effecting an intermediate purging cycle of the discharge duct (28), interrupting the flow of gaseous fuel to the combustor (14), and progressively increasing the value (FSRn) of the flow of gaseous fuel entering the combustor (14), effecting further attempts at ignition until the mixture of air/gaseous fuel has been ignited and the consequent start-up of the turbine (20), or until a predetermined maximum value (FSRmax) of the flow of gaseous fuel has been reached.

Abstract: Gas turbine, computer readable medium, and method for controlling an operating point of the gas turbine that includes a compressor, a combustor and a turbine is provided. The method includes determining a turbine pressure ratio, calculating a primary to lean-lean mode transfer threshold reference curve as a function of the turbine pressure ratio, determining at a first time when an exhaust temperature associated with the operating point is higher than an exhaust temperature of the primary to lean-lean mode transfer threshold reference curve for the same turbine pressure ratio, and changing, after a predetermined time after the first time, a split fuel quantity from a first value to a second value if the exhaust temperature associated with the operating point remains higher than the exhaust temperature of the primary to lean-lean mode transfer threshold reference curve.

Abstract: Gas turbine, software and method for controlling an operating point of the gas turbine that includes a compressor, a combustor and at least a turbine is provided. The method includes determining a turbine exhaust pressure at an exhaust of the turbine; measuring a compressor pressure discharge at the compressor; determining a turbine pressure ratio based on the turbine exhaust pressure and the compressor pressure discharge; calculating an exhaust temperature at the exhaust of the turbine as a function of the turbine pressure ratio; identifying a reference exhaust temperature curve in a plane defined by the exhaust temperature and the turbine pressure ratio; and controlling the gas turbine to maintain the operating point on the reference exhaust temperature curve.

Abstract: Gas turbine and method for controlling an operating point of the gas turbine that includes a compressor, a combustor and at least a turbine. The method includes calculating an exhaust temperature reference curve of the turbine as a function of a turbine pressure ratio; determining whether condition IGVmin+?IGV1?IGVset point?IGVmax+?IGV2, and condition ttx?ttxh+?ttx3, are true; and changing, if both conditions are true, a split fuel quantity from a first value to a second value or otherwise maintaining the first value, the first value characterizing a lean-lean steady state mode and the second value characterizing a premixed secondary mode of a premixed mode.

Abstract: A method is described for the start-up of a gas turbine comprising the phases of effecting a preliminary purging cycle of the discharge duct (28) of the turbine (20), establishing a predetermined minimum value (FSR1) for the flow of gaseous fuel entering the combustor (14) for a period of time which is adequate for effecting a first attempt at ignition and effecting a first attempt at ignition, effecting an intermediate purging cycle of the discharge duct (28), interrupting the flow of gaseous fuel to the combustor (14), and progressively increasing the value (FSRn) of the flow of gaseous fuel entering the combustor (14), effecting further attempts at ignition until the mixture of air/gaseous fuel has been ignited and the consequent start-up of the turbine (20), or until a predetermined maximum value (FSRmax) of the flow of gaseous fuel has been reached.