Abstract: A method of operating a multi-engine aircraft includes operating a first engine of the aircraft to provide motive power; and operating a second engine of the aircraft in a standby mode to provide substantially no motive power, a rotor of the second engine having an idle rotational speed in the standby mode, and in the standby mode, sequentially executing cycles, a given cycle of the cycles including: opening a set of variable guide vanes upstream a compressor section of the second engine, spiking a rate of a fuel flow to a combustor of the second engine, the spiking and the opening timed to increase a rotational speed of the rotor of the second engine to an upper threshold above the idle rotational speed of the rotor, and in response to the rotational speed reaching the upper threshold, at least substantially closing the set of variable guide vanes.

Abstract: A water-injection system for power plants and for injecting water into a steam system includes a supply unit, a metering unit and an injection unit. The supply unit is configured to make water available to the metering unit. The metering unit is in the form of an electrically actuable system and is configured to meter a quantity of water to be injected into the steam system and to make it provide to the injection unit. The injection unit is configured to introduce the water into the steam system.

Abstract: Systems and methods for controlling a gas turbine engine are provided. The system comprises an interface to a fuel flow metering valve for controlling a fuel flow to the engine in response to a fuel flow command and a controller connected to the interface and configured for outputting the fuel flow command to the fuel flow metering valve in accordance with a required fuel flow. The controller comprises a feedforward controller configured for receiving a requested engine speed and acceleration, obtaining a steady-state fuel flow for the requested engine speed and a relationship between fuel flow and gas generator speed, and determining the required fuel flow to obtain the requested engine acceleration as a function of the requested engine speed, the steady-state fuel flow, and the relationship between fuel flow and gas generator speed.

Abstract: A method for improving partial load efficiency in a gas turbine engine including a compressor, burners, a high pressure turbine and a low pressure turbine; including the step of operating the gas turbine engine by regulating at least: air mass flow rate and flame temperature; regulation is carried out by controlling at least: the air mass flow rate supplied to the combustion chamber from the compressor, and the number of operating burners, and the change in enthalpy drop between the high and low pressure turbine to control the air mass flow rate.

Abstract: A compressor has a lower inlet with an intake plenum and an upper outlet with a discharge scroll; the compressor includes a plurality of drainage pipes ending at the intake plenum.

Abstract: Disclosed herein is an integrated power generation and load driving system, comprising in combination a multi-shaft gas turbine engine comprising a high-pressure turbine mechanically coupled to an air compressor; and a low-pressure turbine, fluidly coupled to but mechanically separated from the high-pressure turbine and mechanically coupled to an output power shaft wherein the output power shaft is connected to a shaft line an electric generator, mechanically coupled to the shaft line and driven into rotation by the gas turbine engine a rotating load, mechanically coupled to the shaft line and driven into rotation by the gas turbine engine a load control arrangement, configured for controlling at least one operating parameter of the rotating load to adapt the operating condition of the rotating load to process requirements from a process, whereof the rotating load forms part, while the low-pressure turbine and the electric generator rotate at a substantially constant speed.

Abstract: A variable vane actuator assembly for a gas turbine engine according to an exemplary aspect of the present disclosure includes, among other things, a plurality of vanes. A synchronization rings surrounds and is mechanically linked to drive the vanes to pivot for varying an angle of the vanes. A crank shaft is mechanically linked to the synchronization ring for rotating the synchronization ring. A fluid actuated rotary motor is located at an end of the crank shaft for selectively rotating the crank shaft.

Abstract: The present invention discloses a novel way of controlling a gas turbine engine using detected temperatures and detected turbine rotor speed. An operating system provides a series of operating modes for a gas turbine combustor through which fuel is staged to gradually increase engine power, yet harmful emissions, such as carbon monoxide, are kept within acceptable levels.

Abstract: A two-shaft gas turbine of the present invention, in which a mass flow of an air into a compressor is regulated by controlling a set angle of an inlet guide vane (IGV) on an air intake side of the compressor, comprises, as a device to control the set angle of the IGV, a first controller to control the set angle of the IGV based on a corrected speed of the gas generator shaft during low speed rotation of the gas generator shaft, the corrected speed having been corrected according to an ambient temperature; a second controller to control the set angle of the IGV to maintain a constant actual speed of the gas generator shaft during high speed rotation of the gas generator shaft; and an ambient temperature correction part to increase the actual speed maintained constant by the second controller if the ambient temperature is equal to or more than a threshold value.

Abstract: Provided is a gas turbine capable of achieving high-speed startup of the gas turbine through quick operation control of an ACC system during startup of the gas turbine, improving the cooling efficiency of turbine stationary components, and quickly carrying out an operation required for cat back prevention during shutdown of the gas turbine.

Abstract: A gas turbine and method are disclosed by which the gas turbine can be safely operated at nominal speed with reduced margin to a surge limit of a compressor. The gas turbine, via a directly driven generator which generates alternating current with an operating frequency and which is connected in a frequency-coupled manner to an electricity grid, can deliver electric power to this grid. In the case of an underfrequency event the compressor of the gas turbine is unloaded by controlled, fast closing of the variable compressor guide vanes (VGV) and as a result maintains a sufficient margin to the surge limit of the compressor.

Abstract: A two-shaft gas turbine is provided which includes: a compressor; a combustor having multiple fuel systems and generating combustion gas by combusting fuels from the fuel systems and air compressed by the compressor; a high-pressure turbine coupled coaxially with the compressor and rotated by the combustion gas; a low-pressure turbine having a shaft structure independent of the high-pressure turbine and rotated by exhaust gas from the high-pressure turbine; an air extraction channel for extracting the air compressed by the compressor; an injection flow channel for feeding the air extracted through the air extraction channel back to the combustor; and a controller for controlling the flow rate of the fuel supplied to each of the fuel systems based on the air flow rate of the compressor, on the flow rate of the fuel supplied to the combustor, and on the temperature of the air in the injection flow channel.

Abstract: A refrigeration system includes a chiller having a refrigerant loop. A compressor is part of and in fluid communication with the refrigerant loop. The compressor has two stages, one with a variable geometry diffuser and one with a fixed geometry diffuser.

Abstract: Example computer-implemented methods, apparatuses, and systems are described for implementing split range control using Proportional-Integral (PI) control on a process. In some aspects, a feedback signal from the process is received. A proportional control is performed on the feedback signal to generate a first control output while an integral control is performed on the feedback signal to generate a second control output. A first valve of the process is controlled based on the first control output while a second valve of the process is controlled based on the second control output. The second valve has a valve diameter larger than a valve diameter of the first valve.

Abstract: Methods and systems for determining that a sensor, such as a pressure sensor, that provides feedback on one or more conditions of a gas turbine is deficient are provided. The amplitude of measurements from the sensor may be monitored in different frequency ranges in order to detect certain abnormal conditions of the gas turbine that require attention by the control system in one frequency range, and also, concurrently and/or separately, detect a sensor deficiency in another frequency range prior to actual failure of the sensor, at which time the failure may otherwise be noticeable in the first frequency range. This permits better detection of deficient sensors during operation of the gas turbine.

Abstract: Systems and methods for use in controlling a hydraulically powered AC generator are provided. One control system includes a valve system. The valve system includes a fixed valve configured to provide a substantially constant flow rate of the fluid through the fixed valve to the hydraulically powered AC generator. The valve system further includes a variable valve configured to provide a variable flow rate of the fluid through the variable valve to the hydraulically powered AC generator. The control system further includes a sensor device configured to measure a speed of movement of a component of the hydraulically powered AC generator. The control system further includes a control circuit configured to control the variable flow rate of the variable valve based on the speed of movement of the component measured by the sensor device.

Abstract: Methods and systems are provided for adjusting operation of an electric motor coupled to a compressor at high altitude engine operation. In one example, the method may include adjusting a ratio of electric compressor assist provided by an electric motor to an intake compressor relative to turbine assist provided via a wastegate during engine idling conditions as well as during transmission gearshifts. The method allows for engine idle speed and torque to be maintained at high altitudes while reducing sluggish boost behavior.

Abstract: A method of controlling a speed of a gas turbine engine including a gas generator spool and a power turbine spool rotating independently from one another, including controlling a rotational speed of the gas generator spool according to a fixed relationship with respect to an outside air temperature throughout a variation of output power.

Abstract: A lubrication system for a gas turbine engine includes a variable output lubricant pump operable to supply lubricant to an actuator system.

Abstract: A system includes a turbine combustor, a turbine driven by combustion products from the turbine combustor, and an exhaust gas compressor. The exhaust compressor is configured to compress and route an exhaust gas from the turbine to the turbine combustor. The system also includes an exhaust gas recirculation (EGR) path extending through the exhaust gas compressor, the turbine combustor, and the turbine, a first exhaust gas (EG) extraction port disposed along the EGR path, and a second EG extraction port disposed along the EGR path.

Abstract: A method for controlling a gas turbine including a compressor assembly including at least one variable geometry portion, a combustion chamber, and a turbine assembly. The method generates a flow rate setpoint value for fuel to be fed to the combustion chamber as a function of a desired speed of the gas turbine, computes threshold values for maintaining the fuel flow setpoint value in a given range, the threshold values depending on a thermodynamic state of the gas turbine, and controls the position of the variable geometry portion by controlling an actuator as a function of the difference between position information representative of the instantaneous position and setpoint position information. The threshold values are automatically adjusted by computation in real time as a function of the instantaneous position information of the variable geometry portion or of the difference between this position information and the setpoint position information.

Abstract: A method of controlling a power plant that comprises a working fluid and a recirculation loop, wherein the power plant includes a combustor operably connected to a turbine, the method including the steps of: recirculating at least a portion of the working fluid through the recirculation loop; controlling the power plant such that the combustor at least periodically operates at a preferred stoichiometric ratio; and extracting the working fluid from at least one of a first extraction point and a second extraction point positioned on the recirculation loop during the periods when the combustor operates at the preferred stoichiometric ratio.

Abstract: Certain embodiments of the invention may include systems and methods for controlling an integrated drive train. According to an example embodiment of the invention, a method for controlling a gas turbine drive train includes measuring speed associated with the drive train, controlling fuel flow to a gas turbine based at least in part on a speed command and the measured speed, controlling one or more guide vanes associated with a torque converter based at least in part on the speed command and an expected power output of the torque converter, and selectively coordinating respective torque contributions from the torque converter and the gas turbine.

Abstract: A method for controlling a gas turbine including a compressor assembly including at least one variable geometry portion, a combustion chamber, and a turbine assembly. The method generates a flow rate setpoint value for fuel to be fed to the combustion chamber as a function of a desired speed of the gas turbine, computes threshold values for maintaining the fuel flow setpoint value in a given range, the threshold values depending on a thermodynamic state of the gas turbine, and controls the position of the variable geometry portion by controlling an actuator as a function of the difference between position information representative of the instantaneous position and setpoint position information. The threshold values are automatically adjusted by computation in real time as a function of the instantaneous position information of the variable geometry portion or of the difference between this position information and the setpoint position information.

Abstract: A gas turbine engine valve is disclosed. In one form the valve includes two inlets in fluid communication with an outlet. The valve can include a spool having two lands capable of selectively closing either of the two inlets. The valve can include energy storage devices that initially position the spool within a valve housing. A temperature motor is provided to position the spool based upon a temperature of a mixture of working fluid from the two inlets. A working fluid flowing into the first inlet can be in fluid communication with a second end of the valve; and a working fluid flowing into the second inlet can be in fluid communication with a first end of the valve. A relatively high pressure condition at one or the other of the inlets can be used to alter a position of the valve.

Abstract: In one aspect, power generation is accomplished by capturing off-gas from a wellhead of an oil producing well, sensing a change in pressure from which a change in available off-gas can be determined, and adjusting a torque supplied by a prime mover to a generator responsive to the change in available off-gas to vary an amount of electricity generated by the generator.

Abstract: A gas turbine aircraft engine with power variability is provided. The gas turbine aircraft engine comprises a compressor and a turbine mounted on a common shaft, and, a continuously variable transmission coupled to the shaft for transmitting power to a propulsion load.

Abstract: Systems and methods for supplementing a power system to achieve consistent operation at varying altitudes are disclosed herein. A hybrid power system comprising a single power source driving multiple generators may implement a power recovery turbine to drive a supercharger compressor, which may provide compressed air at increased altitudes. The supplemental power system disclosed herein provides necessary shaft horsepower at high altitudes to drive a generator and produce cooling air.

Abstract: Fuel control systems for use with a gas turbine engines which accounts for real-time thermodynamic engine effects when attempting to match or track the NDOTActual rate to the NDOTDemand rate. The fuel control system includes a mechanism for measuring several engine operating parameters and a mechanism for determining an initial engine fuel demand based on the measured engine operating parameters. The control system further includes a mechanism for estimating, during engine operation and based on the measured operating parameters, the amount of heat transferred between fuel combustion gases and the engine metal and estimating an effective fuel flow adjustment based therefrom. The control system disclosed herein also includes a mechanism for determining a final engine fuel demand based on the initial predicted engine fuel demand and the estimated effective fuel flow adjustment.

Abstract: Systems and methods for supplementing a power system to achieve consistent operation at varying altitudes are disclosed herein. A hybrid power system comprising a single power source driving multiple generators may implement a power recovery turbine to drive a supercharger compressor, which may provide compressed air at increased altitudes. The supplemental power system disclosed herein provides necessary shaft horsepower at high altitudes to drive a generator and produce cooling air.

Abstract: An electromechanical inlet guide vane actuation system includes one or more electric motor driven actuators that are used to appropriately position the inlet guide vanes in a gas turbine engine. The actuation system includes a control circuit that supplies guide vane actuation control signals in response to guide vane position command signals it receives. The guide vane actuation control signals are supplied to one or more electric motors, which position actuators, and thus the inlet guide vanes, to the commanded position.

Abstract: Systems and methods for supplementing a power system to achieve consistent operation at varying altitudes are disclosed herein. A hybrid power system comprising a single power source driving multiple generators may implement a power recovery turbine to drive a supercharger compressor, which may provide compressed air at increased altitudes. The supplemental power system disclosed herein provides necessary shaft horsepower at high altitudes to drive a generator and produce cooling air.

Abstract: In order to limit the flame temperature peaks following sudden load variations, corresponding control is planned of the position of the blades (13) of the distributor with variable geometry, of a single-shaft gas turbine (18); in particular, the control system proposed comprises a direct-action regulator (21) consisting of a calculation unit (22), which implements the simplified running model of the gas turbine (18), and a feedback regulator (20), which makes it possible to recuperate any inaccuracies of the direct-action regulator (21), caused by variations of the performance of the turbine (18), relative to those planned by the model, or caused by modelling errors.

Abstract: A gas turbine engine (10) comprises a first compressor (16), a combustor (22) and a first turbine (24) arranged in flow series. The first turbine (24) is arranged to drive the first compressor (16). The first compressor (16) has variable inlet guide vanes (38) and the first turbine (24) has variable inlet guide vanes (42). A second compressor (48) is arranged upstream of the first compressor (16). An auxiliary intake (12) is arranged upstream of the first compressor (16) and downstream of the second compressor (48). A valve (54) is arranged upstream of the first compressor (16) and downstream of the second compressor (48). The valve (54) is movable between a first position in which the second compressor (48) supplies air to the first compressor (16) and a second position in which the second compressor (48) does not supply fluid to the second compressor (16) and the auxiliary intake (12) supplies fluid to the first compressor (16).

Abstract: A gas turbine engine comprises a centrifugal compressor (4), an air diffuser (8), a heat exchanger (10), combustion apparatus (12), and first and second turbines (14,18). The combustion chamber assembly (22) comprises a primary, a secondary and a tertiary fuel and air mixing ducts (54,78,98). The compressor (4), diffuser (8), primary and secondary fuel and air mixing ducts (54,78) and turbines (14,18) all comprise means (6,8,16,20) for varying the mass flow area at their inlets such that in operation the amount of air mass through each component may be independently variable. Under part power conditions the mass flow is reduced and under full power conditions the mass flow is increased thereby maintaining a substantially constant gas cycle throughout the engine.