Abstract: According to the invention, there is provided a single shaft combined cycle power plant which can quickly switch from single operation of a gas turbine to combined operation of the gas turbine and a steam turbine, and can quickly increase output power, from low power to high power. The single shaft combined cycle power plant includes a means for maintaining the rotation speed of the steam turbine at a speed slower than but near a rated rotation speed when the steam turbine is separated from a coupled unit of a generator and the gas turbine.

Abstract: According to the invention, there is provided a single shaft combined cycle power plant which can quickly switch from single operation of a gas turbine to combined operation of the gas turbine and a steam turbine, and can quickly increase output power, from low power to high power. The single shaft combined cycle power plant includes a means for maintaining the rotation speed of the steam turbine at a speed slower than but near a rated rotation speed when the steam turbine is separated from a coupled unit of a generator and the gas turbine.

Abstract: The minimum fuel flow to a combustor of a gas turbine engine is controlled in response to the combustor inlet temperature T3 in order to provide a FAR stability margin which responds to the combustor inlet temperature. This enables the FAR stability margin to be reduced when the risk of flame out is low, for example when the combustor entry temperature is high, while increasing the FAR stability ratio when the combustor entry temperature is low, ie when the engine is idling or when water is ingested.

Abstract: The invention relates to a method for operating a steam power plant comprising a steam generator and a combustion chamber associated therewith, wherein pre-warmed combustion air is guided therein in addition to a fossil fuel. According to the invention, said plant can be operated with a particularly high efficiency ratio in various operating conditions. As a result, the combustion air is at least partially released after the pre-warming thereof and before the introduction thereof into the combustion chamber. A steam power plant which is particularly suitable for carrying out said method comprises, in addition to a pre-air warmer, an air turbine which is mounted downstream from said pre-air warmer in a fresh air pipe.

Abstract: A method of operating a gas turbine combustion system having reduced emissions and improved flame stability at multiple load conditions is disclosed. The improved combustion system accomplishes this through complete premixing, a plurality of fuel injector locations, combustor geometry, and precise three dimensional staging between fuel injectors. Axial, radial, and circumferential fuel staging is utilized including fuel injection proximate air swirlers. Furthermore, strong recirculation zones are established proximate the introduction of fuel and air premixture from different stages to the combustion zone. Fuel injection staging sequences are disclosed that create the conditions necessary to provide stable combustion and reduced emissions at multiple load conditions.

Abstract: Methods and apparatus for operating a gas turbine engine without sustained detrimental levels of dynamic pressure are provided. The engine includes a combustor. The method includes determining the combustor acoustic level amplitude, comparing the acoustic level to a predetermined upper acoustic limit, and adjusting a fuel flow distribution to the combustor using a closed loop controller to facilitate reducing the acoustic level to a predetermined lower acoustic limit that is less than the upper acoustic limit.

Abstract: A lean premix burner for a gas turbine having at least one fuel supply ring 4 fitted with primary fuel nozzles 8 and additional secondary fuel nozzles 9, and a method of operation for this lean premix burner.

Abstract: An electrical power generating system is driven by a multi-spool gas turbine engine including at least first and second spools. The first spool comprises a turbine and a compressor mounted on a first shaft; the second spool has at least a turbine mounted on a second shaft that is not mechanically coupled to the first shaft. A main generator is coupled with one of the spools, and an auxiliary generator/motor is also coupled with one of the spools. Speed control of each of the generators is employed for controlling operation of the engine. The auxiliary generator/motor can operate in either a generation mode to extract power from its spool or a motor mode to inject power into its spool.

Abstract: A method of synthesizing rotor inlet temperature in a turbine comprising the steps of determining a burner fuel flow (WFGG), a burner inlet pressure (PS32), and a compressor discharge temperature (T3) of a turbine, calculating a ratio unit parameter from the burner fuel flow, the burner inlet pressure, and the compressor discharge temperature, and calculating a synthesized rotor inlet temperature from the ratio unit parameter.

Abstract: The method and apparatus of the present invention discloses a power plant operating at low inlet pressure and temperature using a combination of conventional internal combustion engine techniques and jet engine techniques. The combination of a unique combustion chamber design, a novel variable impedance blade set turbine and a closed loop control system allows a variable resonant frequency for combusted gases. As the resonant frequency is approached a control mechanism uses sensor data to maintain the operating point such that maximum power output is achieved for a given throttle setting. The combination of the unique combustion chamber design, multiple fuel injector/sparking device pairs, finely atomized fuel, excess oxygen and the closed loop control system further provides a very linear power curve with low exit hydrocarbon pollution levels and high fuel efficiency.

Abstract: A method for determining a target exhaust temperature for a gas turbine including: determining a target exhaust temperature based on a compressor pressure condition; determining a temperature adjustment to the target exhaust temperature based on at least one parameter of a group of parameters consisting of specific humidity, compressor inlet pressure loss and turbine exhaust back pressure; and adjusting the target exhaust temperature by applying the temperature adjustment.

Abstract: An aerodynamically stabilized premixing burner includes a swirl generator for the production of a rotating combustion air flow, and a device for the introduction of at least one fuel into this combustion air flow. The burner is advantageously provided with a device for the introduction of an axial air flow into the center of the generated rotational flow. This axial air flow is controllable in order to affect the position and intensity of the flame-stabilizing recirculation zone at the burner mouth.

Abstract: A rotor overspeed protection system for a gas turbine engine controls engine fuel flow to prevent an engine rotor from over-speeding. The engine fuel metering system includes a fuel metering valve in flow communication with a fuel shutoff valve and a fuel bypass valve. The rotor protection system includes an overboost servovalve and a soleniod valve coupled to the fuel metering system and to an independent speed sensing system. In operation, servovalve can control the metered fuel flow to engine independently of the fuel metering valve to facilitate reducing rotor overspeeds and overboosts.

Abstract: A fluidic apparatus for modulating the rate of fuel flow into the combustor of a gas turbine engine. The apparatus includes a fluidic oscillator device (preferably an astable fluidic oscillator, or “flip-flop”) having a supply inlet connected to a fluid fuel source and a pair of outlets one of which is connected to the combustor. The fluidic device operates to output fluid fuel from the outlets alternately, so modulating fuel flow into the combustor.

Abstract: A turbine overspeed control system for a gas turbine electrical powerplant. The powerplant may employ an aeroderivative gas turbine engine for producing electrical power. The overspeed control system preferably comprises a compression relief system and an air directing system. When an overspeed condition of the gas turbine engine is detected, the compression relief system acts to remove air from a combustion section of the engine. Preferably, the air is removed to the atmosphere. The air directing system operates to ensure that air entering a compressor section of the gas turbine engine does not impinge on the blades of a compressor turbine located therein at the optimum angle. The result of operating the compression relief and air directing systems is a reduced combustor efficiency. Consequently, a reduced amount of hot gases are available to drive the turbines of the gas turbine engine, and the rotational speed thereof decreases.

Abstract: A gas turbine combustor that controls flow rate of air flowing into a primary combustion zone for controlling a local fuel-air ratio comprises no sliding portion that is liable to cause sticking or biting of components operating in high temperature, thereby providing a simple, reliable and efficient combustor and a combustion control method thereof. The gas turbine combustor comprising a liner provided in a combustor case and a bypass duct provided in the liner and enabling a control of flow rate of air supplied into a primary combustion zone via a swirler by causing a portion of the air to pass through the bypass duct, further comprises a float, made of a magnetic substance, provided in the bypass duct so as to open and close the bypass duct by the position of movement of the float and an electromagnetic coil provided outside of the combustor case corresponding to the position of the float so as to move the float.

Abstract: Method and arrangement for providing a gas turbine (1) having a first compressor (2), a combustion chamber (16) and a first turbine (11), the turbine being adapted to drive the compressor via a first shaft (10a, 10b). The gas turbine also has a bleed valve (12) arranged upstream of the first turbine for conducting part of a gas compressed by the compressor past it during engine braking. The invention also relates to a method for engine-braking a gas turbine.

Abstract: A computerized system for accurate, independent verification of natural gas fuel flow in order to control H2O injection flows. The H2O is injected into a combustion system to control emissions. The system comprises: receiving gas turbine control parameters from a gas turbine control system; receiving control parameters from a megawatt transducer; calculating values based upon readings from said control system and said megawatt transducer; comparing said values to a megawatt reference curve; detecting an abnormal reading; starting a timing sequence during which said reading is monitored; transferring NOx and H2O water injection control to a megawatt module at completion of said timing sequence; alerting operator said transfer; allowing for return of control to said gas turbine control system once said abnormal reading is corrected.

Abstract: Systems and methods are provided for controlling the rotational speed of a turbogenerator in stand-alone mode to account for a present operating load and a transient reserve capability. A base speed set point may be received, comprising a baseline speed setting for the turbogenerator. A speed offset may be determined comprising an adjustment to the base speed set point required to accommodate the transient reserve capability. An adjusted speed set point may be produced by combining the base speed set point and the speed offset. The rotational speed of the turbogenerator may then be set to the adjusted speed set point.

Abstract: Disclosed herein is a “real time” Time Limited Dispatch (TLD) fault management system and method for evaluating the operational suitability of an engine's electronic control system. The TLD system disclosed herein uses a software algorithm to compute or predict the probability of mission success for a given upcoming mission length (e.g., two hours) and the time remaining to repair control system faults before dispatch is disallowed or the flight suspended, regardless of the probability of success.

Abstract: A system and method for tuning a turbine comprises a turbine controller coupled to the turbine, a first computer system coupled to the turbine controller and located locally to the turbine, and a second computer system for exchanging data with the first computer system. The second computer system is located remotely from the turbine and exchanges data with the first computer system via a network connection such as the internet, an intranet or a virtual private network (VPN). Data relating to a characteristic such as turbine combustion dynamics and/or emissions is transmitted by the first computer system to the second computer system. The second computer system transmits control data over the network connection to the first computer to tune the turbine.

Abstract: An apparatus and method for controlling a gas turbine engine involves calculating a simple corrected speed value for the engine using values of compressor speed and inlet stagnation temperature of the compressor. This simple corrected speed value is then adjusted to take into account the water vapour concentration at the inlet to the compressor. This results in a more accurate value of corrected speed for the compressor, which may be used to modulate the fuel supply to a combustor of the engine or to control the geometry of one or more variable compressors in the engine.

Abstract: A method for operating a gas turbine engine upon the occurrence of an offload condition.

Abstract: In a control method of a gas turbine engine, an engine controller 4 outputs a combustor power command FD based on an engine condition from an engine condition detector 3. Then, a combustion controller 6 determines each fuel flow rate based on the combustion power command FD. The combustor controller 6 overrides each fuel flow rate for a certain period, to realize smooth stage-process.

Abstract: A method for determining a target exhaust temperature for a gas turbine including: determining a target exhaust temperature based on a compressor pressure condition; determining a temperature adjustment to the target exhaust temperature based on at least one parameter of a group of parameters consisting of specific humidity, compressor inlet pressure loss and turbine exhaust back pressure; and adjusting the target exhaust temperature by applying the temperature adjustment.

Abstract: A gas turbine apparatus is provided which comprises a turbine, a combustor for burning a mixture of air and fuel and providing the turbine with a combustion gas to drive it, a generator connected to the turbine to receive rotational force therefrom to generate electric power, a temperature sensor for measuring a temperature of an exhaust gas from the turbine, a temperature setting unit and a power setting unit.

Abstract: Adaptive model-based control systems and methods are described so that performance and/or operability of a gas turbine in an aircraft engine, power plant, marine propulsion, or industrial application can be optimized under normal, deteriorated, faulted, failed and/or damaged operation. First, a model of each relevant system or component is created, and the model is adapted to the engine. Then, if/when deterioration, a fault, a failure or some kind of damage to an engine component or system is detected, that information is input to the model-based control as changes to the model, constraints, objective function, or other control parameters. With all the information about the engine condition, and state and directives on the control goals in terms of an objective function and constraints, the control then solves an optimization so the optimal control action can be determined and taken.

Abstract: Disclosed is an engine surge avoidance system and method which adapts the acceleration schedules (i.e., P2.5 bleed valve and NDOT) to prevent engine surge events from occurring while minimizing reductions in engine response time. The surge avoidance system and method disclosed herein achieves this goal by adapting both the NDOT and the P2.5 bleed schedules in an optimum fashion.

Abstract: A method of operating a gas turbine combustion system having reduced emissions and improved flame stability at multiple load conditions is disclosed. The improved combustion system accomplishes this through complete premixing, a plurality of fuel injector locations, combustor geometry, and precise three dimensional staging between fuel injectors. Axial, radial, and circumferential fuel staging is utilized including fuel injection proximate air swirlers. Furthermore, strong recirculation zones are established proximate the introduction of fuel and air premixture from different stages to the combustion zone. Fuel injection staging sequences are disclosed that create the conditions necessary to provide stable combustion and reduced emissions at multiple load conditions.

Abstract: An operation control apparatus and an operation control method for a single-shaft combined plant are provided. A clutch is engaged and disengaged, whereby a gas turbine (power generator) is connected to and disconnected from a steam turbine. The opening of IGV is controlled by an opening command, the opening of a burner bypass valve is controlled by another opening command, and the openings of fuel flow control valves are controlled by other opening commands found based on a pilot ratio. The commands to the IGV and the burner bypass valve and the pilot ratio are found during an isolated operation in which only the gas turbine is operated, during a joint operation in which the gas turbine and the steam turbine are both operated, during a transition from the isolated operation to the joint operation, and during a transition from the joint operation to the isolated operation.

Abstract: A gas turbo group has a combustion chamber comprising a catalytic burner stage (2), a preburner stage (1) located upstream from the catalytic burner stage, as well as a non-catalytic burner stage (11, 5, 6) located downstream from the catalytic burner stage. The preburner stage serves to always maintain a temperature (T1) at the inlet into the catalytic stage that corresponds at least to a minimum temperature (TMIN) necessary for operating the catalytic burner stage. According to the invention, the gas turbo group is operated so that the burner stage located downstream from the catalytic combustion chamber is taken into operation only when the temperature (T2) at the outlet from the catalytic stage has reached an upper limit in the presence of a maximum combustion air mass flow.

Abstract: A fuel delivery system provides for closed loop mass flow control of fuel between a metering valve and a pump, such as a variable delivery pump. Changes in pressure across the metering valve are monitored and pump operation is altered in response thereto. A thermal controller monitors fuel temperature and recirculates a portion of the fuel flow through a heat exchanger. The fuel delivery system can be provided as original equipment or as a retrofit.

Abstract: In a method for increasing the power output of a combined-cycle power station, comprising at least one gas turbo group, at least one heat recovery steam generator and at least one steam turbo group, with the gas turbo group comprising at least one compressor, at least one combustion chamber and at least one gas turbine, the heat recovery steam generator having at least one pressure stage and the steam turbo group comprising at least one steam turbine, in which combined-cycle power station air is compressed in a compressor, is then supplied as combustion air to a combustion chamber, the hot gas which is produced there is passed to a gas turbine, and the exhaust gas from the gas turbine is used in a heat recovery steam generator to produce steam for a steam turbo group, an immediate and rapid increase in the power output is achieved, and an additional power output from the combined-cycle power station is maintained in safe operating conditions, in that an supplemental firing is arranged to provide additional he

Abstract: A method of controlling a gas turbine engine to provide protection against damaging pressure transients in the combustion process and to ensure compliance with emission requirements. Pressure fluctuations are monitored in a plurality of frequency ranges, and unacceptable pressure transients in different frequency ranges trigger different corrective actions. Unacceptable pressure transients in low and intermediate frequency ranges trigger a change in the pilot fuel fraction of a dual-mode combustor, while unacceptable pressure transients in a high frequency range trigger immediate power reduction in the engine. A control system for a gas turbine engine includes a plurality of timers for defining consecutive time periods for alternate monitoring of pressure transients and not monitoring pressure transients. Corrective action is taken only if unacceptable pressure transients are detected in each of the monitored time periods.

Abstract: A gas turbine engine system comprises a first compression stage; a second compression stage; a combustor; a controller; a first sensor for sensing the speed of the first compression stage and providing a first indication of the sensed speed to the controller; and a second sensor for sensing the speed of the second compression stage and providing a second indication of the sensed speed to the controller, wherein the controller is operable to control the supply of fuel to the combustor in dependence upon the first indication received from the first sensor and the second indication received from the second sensor. This arrangement is particularly useful in controlling the acceleration of an aero-engine from minimum idle.

Abstract: A method of operating a turbine arranged in a compressed air energy storage power generation plant comprises an open-loop control of an air mass flow applied within a lower turbine speed range and a closed-loop control of the turbine speed within a higher turbine speed range. The open-loop control comprises the control of the air mass flow by means of air inlet valves and a free development of the turbine speed. The closed-loop control comprises the control of the turbine speed by means of a speed controller, which is acted upon by a speed limiting value determined according to the current air mass flow and a windage calculation. The speed controller activates a static frequency converter in the case that the turbine speed reaches values that are critical with respect to turbine windage or rotor dynamics.

Abstract: A process for increasing the specific output of a combined cycle power plant and providing flexibility in the power plant rating, both without a commensurate increase in the plant heat rate, is disclosed. The present invention demonstrates that the process of upgrading thermal efficiencies of combined cycles can often be accomplished through the strategic use of additional fuel and/or heat input. In particular, gas turbines that exhaust into HRSGs, can be supplementally fired to obtain much higher steam turbine outputs and greater overall plant ratings, but without a penalty on efficiency. This method by and large defines a high efficiency combined cycle power plant that is predominantly a Rankine (bottoming) cycle. Exemplary embodiments of the present invention include a load driven by a topping cycle engine, powered by a topping cycle fluid which exhausts into a heat recovery device.

Abstract: An apparatus estimates governor dynamics for a gas turbine engine used in a system. The apparatus is programmed to obtain a first set of parameters from a governing sub-system coupled to the system, obtain a second set of parameters from the governing sub-system, and generate governor dynamics estimates by utilizing the first and second sets of parameter outputs to solve a multiple objective optimization algorithm problem.

Abstract: In a fuel control method for a combined plant, when the combined plant is just started or during a rated operation, a clutch is completely disengaged or engaged, and therefore, fuel is controlled in the same manner as in the prior art. In the meantime, before and after the clutch is engaged or disengaged, a target load set value is switched to an actual load in response to a signal from a clutch engagement or disengagement period detection unit as a trigger. In this manner, a sudden change in load that may occur when the clutch is engaged or disengaged never influences on a control system disposed downstream thereof.

Abstract: A rotor overspeed protection system for a gas turbine engine controls engine fuel flow to prevent an engine rotor from over-speeding. The engine fuel metering system includes a fuel metering valve in flow communication with a fuel shutoff valve and a fuel bypass valve. The rotor protection system includes an overboost servovalve and a soleniod valve coupled to the fuel metering system and to an independent speed sensing system. In operation, servovalve can control the metered fuel flow to engine independently of the fuel metering valve to facilitate reducing rotor overspeeds and overboosts.

Abstract: In a gas turbine having a combustion chamber (6) and a first row of guide vanes (3) arranged on the outflow side of the combustion chamber (6), a plurality of temperature sensors (8) for measuring temperature value, and a plurality of means (7;71,72,73,74,75,76) for introducing fuel into the combustion chamber (6), which means can be controlled on the basis of the temperature values, the temperature sensors (8) are spectrometers, are designed to measure a combustion-gas temperature and are arranged so as to measure a gas temperature which prevails immediately in front of the first row of guide vanes (3).

Abstract: A fuel ratio control method and a device therefor in a gas turbine combustor are provided in which supply ratio of pilot fuel to main fuel is appropriately maintained to thereby avoid unstable combustion, such as combustion vibration or misfire, and to realize a low NOx combustion. Fuel ratio control signal CSO is set corresponding to generator output LGEN put out by a generator output input unit 1. Pilot fuel ratio control is performed by correcting the fuel ratio control signal CSO corresponding to condition change in both or either one of combustion air and fuel. The condition change in the combustion air is at least one of changes in compressor on-line vane washing, ambient humidity, ambient pressure, etc. and the condition change in the fuel is a change in fuel component. The signal correction is also made by gas turbine deterioration factor or change rate in the generator output.

Abstract: The invention relates to a fuel supply system (1) that supplies a fuel to a burner arrangement (8) with at least one burner (7), in particular a gas turbine (10). The fuel supply system (1) has at its input a control valve (3) that feeds the fuel into the fuel supply system (1) as a function of its actuation. As a function of a requested burner output, a first setpoint is determined for a fuel mass flow with which the burner arrangement (8) must be supplied in order to be able to furnish the required burner output. As a function of this first setpoint of the fuel mass flow a second setpoint is determined for the fuel mass flow, which is fed into the fuel supply system (1) by an actuation of the control valve (3). The second setpoint of the fuel mass flow is selected such that the fuel supply system (1) fed therewith supplies the burner arrangement (8) with the first setpoint of the fuel mass flow.

Abstract: A control system is disclosed for optimizing the transient response of a gas turbine engine by controlling the variable positioning of compressor inlet guide vanes. The system employs a normal mode schedule which schedules relatively closed inlet guide vane settings at low compressor speeds and relatively open inlet guide vane settings at high compressor speeds. The system further employs an alternate mode schedule that schedules inlet guide vane settings that are more closed at low compressor speeds than those scheduled by the normal mode schedule. Control logic is provided for rapidly moving the inlet guide vanes from the more closed settings of the alternate mode schedule to settings which are more open than those which are schedule by the normal mode schedule, during an acceleration from low engine power levels. The control logic is further configured to command the inlet guide vanes back to the normal mode schedule as the acceleration nears completion.

Abstract: Adaptive model-based control systems and methods are described so that performance and/or operability of a gas turbine in an aircraft engine, power plant, marine propulsion, or industrial application can be optimized under normal, deteriorated, faulted, failed and/or damaged operation. First, a model of each relevant system or component is created, and the model is adapted to the engine. Then, if/when deterioration, a fault, a failure or some kind of damage to an engine component or system is detected, that information is input to the model-based control as changes to the model, constraints, objective function, or other control parameters. With all the information about the engine condition, and state and directives on the control goals in terms of an objective function and constraints, the control then solves an optimization so the optimal control action can be determined and taken.

Abstract: In accordance with one aspect of the present invention, in a control system for controlling a gas turbine engine, there is provided a system and a method for determining an optimized output shaft speed for a required thrust and setting an appropriate engine power. The method comprises the steps of: providing a required thrust value at a particular flight condition; determining input values for each of a power, output shaft speed, airspeed, and altitude; determining whether the required thrust is a low power condition; if the required thrust is a low power condition, determining a reduced propeller speed value from the input values and the required thrust value; at least one of increasing and decreasing the optimized output shaft speed using the reduced propeller speed value.

Abstract: A method and apparatus for controlling a turbo-machine in case of failure of the main burn fuel flow calculator. The apparatus receives at least information from various sensors as well as from the main burn fuel flow calculator. The method and apparatus, herein disclosed, provides a smooth and secure transition between the last burn fuel flow value before the failure of the main burn fuel flow calculator and the future burn fuel flow values.

Abstract: This invention is a fuel injection control system for a turbine engine. The invention uses at least one fuel injector, having means for injecting fuel in pulses to the combustion chamber of a turbine engine, and an electronic control unit to receive and interpret input sensor signals from selected operating functions of the engine and to generate and direct fuel injection signals to modify the pulse duration and/or frequency of fuel injection in response to a deviation from a selected operating function, such as the desired operating speed, caused by variable operating loads encountered by the turbine engine. This configuration provides significantly greater fuel efficiency, better operational control and response time, and a lighter weight than is currently available in turbine engines. The invention may be used in many applications such as commercial, private, experimental and military aviation, power plant turbines, and other industrial, military and mining applications.

Abstract: A method of controlling a gas turbine engine to provide protection against damaging pressure transients in the combustion process and to ensure compliance with emission requirements. Pressure fluctuations are monitored in a plurality of frequency ranges, and unacceptable pressure transients in different frequency ranges trigger different corrective actions. Unacceptable pressure transients in low and intermediate frequency ranges trigger a change in the pilot fuel fraction of a dual-mode combustor, while unacceptable pressure transients in a high frequency range trigger immediate power reduction in the engine. A control system for a gas turbine engine includes a plurality of timers for defining consecutive time periods for alternate monitoring of pressure transients and not monitoring pressure transients. Corrective action is taken only if unacceptable pressure transients are detected in each of the monitored time periods.

Abstract: The present invention is directed to a fluidic system and method for controlling the airflow to a lean premix combustor. The system and method as disclosed allow for reduced power, which results in reduced emissions, while at the same time providing excellent performance. This is accomplished through the use of fluidic means, which do not have the problems associated with hot moving parts of prior art mechanical means. Specifically, the introduction of an airflow downstream from openings in the dilution section cause a local boundary layer separation forcing air into the dilution holes.