Abstract: Methods, apparatus, systems and articles of manufacture are disclosed for closed loop control of a gas turbine. An example apparatus includes a frequency band splitter to separate a combustion pulsation signal into a plurality of frequency bands. The example apparatus includes a plurality of subcontrollers, each subcontroller corresponding to one of the frequency bands. Each subcontroller is to be activated at an amplitude threshold associated with the normal operating set point of the frequency band and to generate a correction value while the corresponding frequency band is operating beyond the amplitude threshold. The example apparatus includes a net correction output calculator to aggregate the correction values to generate an aggregated correction value.

Abstract: A gas turbine control device for a gas turbine system includes a sensing unit for measuring the rotor speed and the output of the power generator; a speed regulation rate setting unit for calculating an actual speed regulation rate based on the measured rotor speed and the measured output of the power generator, and for setting a reference speed regulation rate based on the actual speed regulation rate and the target speed regulation rate; and a fuel amount control unit for controlling an amount of fuel supplied to the combustor based on the set reference speed regulation rate. Stable system operation is secured by a method of controlling the gas turbine system to satisfy a target speed regulation rate if additional power should be supplied due to sudden load fluctuations or a failure at another power plant.

Abstract: A gas turbine engine and method of operation are provided. The gas turbine engine may include a variable geometry component operably driven by a component actuator. The component actuator may be in fluid communication with a primary line having a valve associated therewith. The method may include determining a demand pressure associated with actuating the variable geometry component using the component actuator. The method may also include adjusting a position of the valve based on the demand pressure to generate a fuel pressure at the component actuator that is greater than or equal to the demand pressure.

Abstract: One aspect is a flight control system for a rotary wing aircraft that includes flight control computer configured to interface with a main rotor system, a translational thrust system, and an engine control system. The flight control computer includes processing circuitry configured to execute control logic. The control logic includes a primary flight control configured to produce flight control commands for the main rotor system and the translational thrust system. Main rotor engine anticipation logic is configured to produce a rotor power demand associated with the main rotor system. Propulsor loads engine anticipation logic is configured to produce an auxiliary propulsor power demand associated with the translational thrust system. The auxiliary propulsor power is combined with the rotor power demand to produce a total power demand anticipation signal for the engine control system.

Abstract: A method includes instructing a purge valve of a gas turbine system to open, thereby purging a fuel circuit by filling the fuel circuit with purge gas, wherein the fuel circuit initially contains fuel. The method also includes generating a model of the gas turbine system that simulates a modeled output based on a model input corresponding to a measured input. The method further includes receiving a measured output of the gas turbine system. The method also includes adjusting the model input such that the modeled output more closely matches the measured output when the measured output is not approximately equal to the modeled output. The method further includes instructing the purge valve to open during a subsequent purge operation and a gas control valve to open more fully or at least partially close during the subsequent purge operation based at least in part on adjusting the model input.

Abstract: A system for a gas turbine includes a control system comprising a processor. The processor is configured to receive a signal indicating spray intercooling fluid demand of the gas turbine. The processor is configured to determine a rate of change of the spray intercooling fluid demand. The processor is configured to control flow of a nitrogen oxide (NOX) minimization fluid that reduces NOX emissions from the gas turbine based at least in part on the rate of change of the spray intercooling fluid demand.

Abstract: An operating method for a gas turbine by partial-load operation, includes setting of a power setpoint value for a predefined temperature value; determining the two operating curves as a function of temperature according to the power of the gas turbine, wherein the power setpoint value is located between said operating curves; determining the difference in power of said two operating curves at the substantially constant predetermined temperature value; determining a power deviation from the predetermined power setpoint value of one of the two operating curves at the substantially constant predetermined temperature value; calculating an interpolated operating curve deviation on the basis of the difference in power and the power deviation, wherein the temperature is a turbine outlet temperature or a computationally determined turbine inlet temperature.

Abstract: The method effects control upon engines, in particular to regulating power of a gas-turbine-generator system used in gas-turbine locomotives, hybrid locomotives, etc. A control signal for the fuel metering unit actuator is formed by an electronic engine control system on the basis of processing of a signal from a turbine rpm sensor and a design value of the generator active electric output power. The system power can be preset. A preset power value is compared to a real power calculated value which is obtained according to measured values of current and voltage. An obtained difference is taken as the basis for forming a control signal for the fuel metering unit actuator in order to provide a certain turbine rpm and a control signal for a current regulator supplying energy to the generator excitation winding in accordance with the load curve of the gas turbine-generator system.

Abstract: According to the embodiment of the present invention, there are provided a first stage auxiliary burner configured to heat up the exhaust gas in the upstream side of the superheater, a second stage auxiliary burner configured to heat up the exhaust gas in the upstream side of the evaporator, a fuel supply system configured to distribute fuel so as to be supplied to the first stage auxiliary burner and the second stage auxiliary burner. Distribution of fuel charged to each of the first stage auxiliary burner and the second stage auxiliary burner is controlled in accordance with a predetermined distribution ratio of each charging quantity to whole charging quantity in all the range thereof.

Abstract: The disclosure relates to optimization of gas turbine power plant response during power system transients. In certain embodiments, systems, methods, and apparatus can control a power generating system by using the reactive components of the current and the reactive components of the voltage and the magnitude of the voltage at the generator terminals of a gas turbine generator system. In one embodiment, a system can identify a power system fault based on at least three conditions occurring for a specified duration and at substantially the same time: (1) an increase in the reactive current, (2) a decrease in the magnitude of the voltage, and (3) an increase in the reactive power. In one embodiment, a power system can further detect a remote breaker open (RBO) condition, and distinguish a RBO condition from a power system fault condition.

Abstract: A system and methods of estimating and controlling fuel flow in a gas turbine engine are disclosed. The system and methods include providing a metering valve and a pressure regulating valve. The system and methods further include determining a differential pressure error of the pressure regulating valve based on a metering valve inlet pressure, a discharge pressure, and a bypass fuel flow and determining a metering valve fuel flow based on a metering valve position and the differential pressure error.

Abstract: A method of making safe operation of a rotary assembly of a turbomachine including a turbine and a rotary machine, the method anticipating an event of exceeding a predetermined threshold speed by repetitively performing a prediction cycle including: measuring magnitudes relating to operation of the turbomachine, including real speed of rotation of its rotary assembly; based on the magnitudes, estimating driving and resisting torques applied to the rotary assembly; preparing a representative value representative of the difference between these two torques; and calculating a predicted speed of rotation for the rotary assembly at a given time horizon based on the representative value and the real speed of rotation. An action is taken on the operation of the turbomachine to limit an extent to which its rotary assembly exceeds the threshold speed in the event of the predicted speed of rotation exceeding the threshold speed.

Abstract: A system and methods are provided for controlling turboshaft engines. In one embodiment, a method includes receiving input signals for a collective lever angle (CLA) command and real-time power turbine speed (NP) of an engine, determining system data for engine effectors by the control unit based on the input signals for the collective lever angle (CLA) command and the real-time power turbine speed (NP) based on an integrated model for the turboshaft engine including a model of a gas generator section of the turboshaft engine and a model of a power turbine and rotor load section of the turboshaft engine. The method may also include determining control output based on model-based multi-variable control including optimization formulation and a constrained optimization solver. The method may also include outputting one or more control signals for control of the turboshaft engine.

Abstract: Distributed fuel control system and methods are disclosed. A distributed fuel control system may comprise a controller, a fuel delivery system, and fuel delivery system sensors and combustion sensors. The controller may output a control signal in response to at least one of the fuel delivery system sensor or the combustion sensors. In response, the fuel flow to individual multiplex fuel delivery unit may be controlled according to various methods. One such method includes determining a desired fuel pressure differential, directing a torque motor to set a pressure regulator to a position corresponding to the desired fuel pressure differential, determining a sensed fuel pressure differential, and adjusting the torque motor in response to a difference between the sensed fuel pressure differential and the desired fuel pressure differential.

Abstract: In one embodiment, a relational database is structured so that elements and alternatives directly reference parameter values stored in a unitized data store. No intermediary tables are required between the elements, the alternatives, and the parameter values. Further, a level tracking mechanism is employed among alternatives that allows for efficient bulk-data retrieval, for example, via a single database query. In one type of operation, an element of a system model is accessed. A selected scenario is accessed that references a plurality of alternatives that exist among a larger plurality of alternatives. Parameter values are retrieved from the unitized data store based on a direct reference from the element and a referenced alternative of the selected scenario. The unitized data store includes values for the larger plurality of alternatives. The retrieved parameter values are used in executing the system model.

Abstract: A method for regulating a gas turbine wherein the fuel quantity supplied to the burners of the gas turbine is regulated using a target value for the corrected turbine outlet temperature. A stable operation of the gas turbine is to be allowed with a particularly high degree of efficiency and a high output at the same time. The target value for the corrected turbine outlet temperature is set using a value which characterizes the combustion stability in the burners, wherein the target value for the corrected turbine outlet temperature is set additionally using the surrounding temperature. Furthermore, the target value for the corrected turbine outlet temperature is set only below a specified surrounding temperature using the value which characterizes the combustion stability in the burners.

Abstract: The present disclosure generally relates to internal combustion engines. The teachings thereof may be embodied in methods for the measuring of a feedback signal generated by the movement dynamics of a fuel injector in operation. A method may include: (a) generating an electrical test pulse; (b) feeding the test pulse into an actuation line connecting the output stage to the injector to an electric drive of the injector; (c) measuring an electrical response pulse generated by the actuation line in response to the test pulse; (d) identifying a characteristic feature of the measured response pulse; (e) transferring the feature to a control and evaluation unit; (f) evaluating the feature; and (g) acquiring the characteristic information item about the measuring channel based on the evaluation of the transferred characteristic feature.

Abstract: A system for determining a deceleration rate of an aircraft, in various embodiments, includes at least one component capable of transmitting a first deceleration rate. The system also includes a brake control unit coupled to the at least one component and having a brake controller that is configured to receive the first deceleration rate from the at least one component and to determine a likely accurate deceleration rate based on the first deceleration rate, a second deceleration rate and a hierarchy of sources of deceleration rates.

Abstract: A combustion staging system has a splitting unit receiving and splitting metered fuel flow into out-going pilot and mains flows; pilot and mains fuel manifolds receiving the pilot and mains flows; and parallel mains flow scheduling valves distributing the mains flow. The mains flow scheduling valves pass the pilot fuel flow to injector pilot discharge orifices. Each mains flow scheduling valve has a chamber containing a piston, the chamber to a piston pilot side communicating with the pilot fuel manifold and the chamber to a mains side of the piston communicating with the mains fuel manifold. The piston is biased towards a closed pilot-only position preventing flow out of the chamber mains side to the injector mains discharge orifice. The piston is movable under increased pressure in the mains fuel manifold to an open pilot-and-mains position allowing flow out of the chamber mains side to the injector mains discharge orifice.

Abstract: The present disclosure relates generally to system and method for detecting fuel shutoff valve failures in a system including multiple fuel shutoff valves connected in series. By commanding different fuel shutoff valves to close and detecting changes in the system operating conditions, the system and method may determine if any of the fuel shutoff valves are not working properly.

Abstract: The present disclosure provides a tuning system for tuning the operation of a gas turbine. The system comprises operational turbine controls for controlling operational control elements of the turbine, including at least one of turbine fuel distribution or the fuel temperature. The system also has a tuning controller communicating with the turbine controls. The tuning controller is configured to tune the operation of the turbine in accordance with the following steps: receiving operational data about the turbine, providing a hierarchy of tuning issues, determining whether sensed operational data is within predetermined operational limits and producing one or more indicators. If the operational data is not within predetermined operational limits, the tuning controller will rank the one or more indicators to determine dominant tuning concern, and tune the operation of the turbine based on dominant tuning concern. Also provided herein are a method and computer readable medium for tuning.

Abstract: A method and system for transitioning a gas turbine from burning gaseous fuel to liquid fuel and purging the liquid fuel therefrom after transfer back to the gaseous fuel are disclosed herein. The method includes pressurizing a volume of liquid fuel in an accumulator with a first volume of motive gas. A valve is opened in response to low gaseous fuel pressure in the gas turbine to permit the volume of liquid fuel to flow through a conduit to the gas turbine. A volume of flushing medium is pressurized in the accumulator with a second volume of motive gas. The valve is opened to permit at least a portion of the volume of flushing medium to flow through the conduit to flush any of the volume of liquid fuel remaining in the conduit after the gas turbine consumes the volume of liquid fuel.

Abstract: Methods and apparatus for controlling multiple valves as a single valve based on a coordinated control signal are disclosed. In some examples, an apparatus includes a valve controller to be operatively coupled to a first valve and a second valve. In some examples, the second valve is to be operatively positioned in series with the first valve. In some examples, the valve controller is to control a position of the first valve and a position of the second valve based on a coordinated control signal to be received by the valve controller.

Abstract: A power plant for an aircraft such as an unmanned aero vehicle in which a gas turbine engine drives an electric generator to produce electrical power for a system load of the aircraft. An engine control unit monitors engine performance and regulates engine power output through fuel flow control to a combustor. A power control module regulates power output of the generator to the system load and to a battery through a bus. A pulse width modulation is used between the power control module and the bus to optimize performance of the gas turbine engine instead of adjusting fuel flow to the combustor.

Abstract: A gas turbine engine assembly is provided having a gas turbine engine and a fuel supply in flow communication with the gas turbine engine. An accumulator is positioned in flow communication between the fuel supply and the gas turbine engine to store fuel pressure in fuel flowing from the fuel supply to the gas turbine engine.

Abstract: An analog output stage of a field device employed in process automation is provided. The analog output stage regulates an analog output, for example, a loop current flowing in a two wire current loop, based on an input, for example, a process variable such as temperature, pressure, etc., detected by the field device. The analog output stage includes a regulator module and a switching module. The switching module, via a switching pulse width modulated signal, alternately applies to the regulator module, a first analog value associated with the input detected by the field device and a predefined analog output, and a second analog value associated with the analog output. The regulator module includes an integrator and a differential amplifier. The regulator module generates a differential analog output based on the first analog value and the second analog value and regulates the analog output based on the differential analog output.

Abstract: A gas turbine engine is provided with a controller configured to detect a spool shaft failure and to initiate an engine shut-down in response to the shaft failure. The controller evaluates the compressor speed probe, the speed probe continuity, P30 pressure and compressor surge to determine whether a shaft failure has occurred.

Abstract: A device for determining a fuel split, and particularly a final fuel split in at least one staged combustion chamber of a gas turbine or an aircraft engine is provided. The device comprises a first control device for determining a preselected fuel split demand for the staged combustion chamber, wherein this determination can be performed based on the detection of a steady state or the detection of a transient state. The detection can in particular be performed based on a combustion chamber exit temperature, a turbine input temperature and/or a value for the fuel/air ratio.

Abstract: A stroke transmitter is presented. The stroke transmitter includes a conduit for providing a passage to a fluid, an actuating unit for increasing pressure in an hydraulic fluid, a valve unit configured to operate depending on the pressure of the hydraulic fluid, the valve unit arranged inside the conduit to regulate a flow of the fluid, and a pipe connecting the actuating unit and the valve unit for communicating the pressure of the hydraulic fluid between the actuating unit and the valve unit. The actuating unit is arranged outside the conduit.

Abstract: A method of controlling a flow of a fuel mixture of different types of fuel in a gas turbine engine is described which includes determining a combustive energy value of an input of the fuel mixture in the engine, extracting fuel schedule data from a fuel schedule established for a reference fuel, determining a desired fuel mixture flow rate by adapting the fuel schedule data to the fuel mixture based on the combustive energy value, and controlling a fuel metering device of the engine such that the fuel mixture flow rate corresponds to the desired fuel mixture flow rate.

Abstract: Embodiments of the disclosure relate to performance testing of a gas turbine. In one embodiment, a gas turbine performance testing system can include a server, a transducer system, a signal converter, and an automated gas chromatograph. The transducer system acquires one or more functional parameters of the gas turbine and the signal converter converts the functional parameters acquired by the transducer system to gas turbine operational data. The automated gas chromatograph automatically analyzes a test sample of a natural gas that is used to operate the gas turbine. The gas turbine operational data generated by the signal converter and the analysis information obtained from the test sample are provided to the server for propagating via a communication network, to a client computer where the gas turbine operational data and the analysis information can be used to obtain a gas turbine performance test result.

Abstract: A method and apparatus for detecting the current damaged state of a machine is provided.

Abstract: An airflow control system for a combined cycle turbomachine system according to an embodiment includes: an airflow generation system for attachment to a rotatable shaft of a gas turbine system, the airflow generation system drawing in an excess flow of air through an air intake section; a mixing area for receiving an exhaust gas stream produced by the gas turbine system; an air extraction system for extracting a first portion of the excess flow of air to provide bypass air, and for diverting the bypass air into the mixing area to reduce a temperature of the exhaust gas stream; diverting a second portion of the excess flow of air into the compressor component; and in response to an increase in a temperature of the air, increasing the second portion of the excess flow of air diverted into the compressor component.

Abstract: A method of evaluating a part is characterized by obtaining data representing a distress rank model (DRM) and a cumulative damage model (CDM) for the part. Based on the data, the method ascertains a DRM value for the part and a CDM value for the part. The method determines whether the DRM value is at or above a predetermined DRM threshold and whether a CDM value is at or above a predetermined CDM threshold. If either the DRM value or the CDM value is at or above at least one respective threshold, an action related to the part is generated.

Abstract: A system and medium for controlling a fuel gas compressor of a gas turbine system that compresses a gaseous fuel for consumption in a high-pressure combustor. Moreover, the compressor is configured to generate a discharge pressure for the combustor based at least in part on a load demand for the gas turbine system.

Abstract: One example aspect of the present disclosure relates to a method. The method can include receiving, by one or more computing devices, an input related to power consumption. The method can include filtering, by the one or more computing devices, the received input. The method can include classifying, by the one or more computing devices, the filtered input into one zone of a plurality of zones. The method can include determining, by the one or more computing devices, a setting associated with the classified zone. The setting can determine power production during an idle setting. The method can include causing, by the one or more computing devices, an adjustment to the determined setting at a rate determined by a rate limit.

Abstract: A filter algorithm for a dual channel electronic engine control system according to one disclosed non-limiting embodiment of the present disclosure includes a division function that divides a measured pressure rate of change of one of a FADEC channel A and FADEC channel B by an average pressure of the FADEC channel A and the FADEC channel B to obtain a resultant value; a first comparator function to bound a proper high resultant value from the division function; a second comparator function to bound a proper low resultant value from the division function; and an OR gate in communication with the first comparator and the second comparator such that if an output from either the first comparator function and the second comparator function is true, that one of the FADEC channel A and the FADEC channel B is filtered out for a time period.

Abstract: A method of managing a gas turbine engine includes the steps of detecting an airspeed and detecting a fan speed. A parameter relationship is referenced related to a desired variable area fan nozzle position based upon at least airspeed and fan speed. The detected airspeed and detected fan speed is compared to the parameter relationship to determine a target variable area fan nozzle position. An actual variable area fan nozzle position is adjusted in response to the determination of the target area fan nozzle position and at least one threshold.

Abstract: A system includes an emissions control system. The emissions control system includes a processor programmed to receive one or more selective catalytic reduction (SCR) operating conditions for an SCR system. The SCR system is included in an aftertreatment system for an exhaust stream. The processor is also programmed to receive one or more gas turbine operating conditions for a gas turbine engine. The gas turbine engine is configured to direct the exhaust stream into the aftertreatment system. The processor is further programmed to derive a NH3 flow to the SCR system based on an SCR model and the one or more SCR operating conditions, to derive a NO/NOx ratio, and to derive a fuel split for the gas turbine engine based on the NH3 flow, the NO/NOx ratio, or a combination thereof.

Abstract: The subject matter of this specification can be embodied in, among other things, a method that includes receiving, at a ratio controller, turbine response values based on first process output value based on a first control parameter and a first process input value, and a second process output value based on a second control parameter and a second process input value, providing the first process input value as a predetermined first constant set point value while varying the second process input value, receiving updated turbine response values, determining at least one third control parameter, providing the third control parameter as the second control parameter, providing the second process input value as a predetermined second constant set point value while varying the first process input value, receiving updated turbine response values, determining at least one fourth control parameter, and providing the fourth control parameter as the first control parameter.

Abstract: A method for correcting a fuel quantity injected by a fuel injection device during operation of an internal combustion engine, including: determining an air heat characteristic variable, on which an air heat stream fed to a combustion chamber of the engine functionally depends; determining an exhaust heat characteristic variable, on which an exhaust heat stream discharged from the combustion chamber functionally depends; determining a heat distribution factor, which specifies a fraction of the exhaust heat stream reduced by the air heat stream in relation to a heat stream fed with the injected fuel to the combustion chamber; calculating a fuel mass fed to the engine from the air heat characteristic variable, the exhaust heat characteristic variable and the heat distribution factor; calculating a comparison variable by comparing the calculated fuel mass with a fuel mass setpoint value and adapting actuation of the fuel injection device depending on the comparison variable.

Abstract: A dilution hole assembly is provided for a combustor. The dilution hole assembly includes a first wall and at least one outer vane. The first wall extends continuously about a centerline and defines a radially inward hole. The at least one outer vane projects radially inward from the first wall for swirling at least a portion of air flowing through the hole.

Abstract: A twin-shaft gas turbine can be used for 50 and 60 Hz power generation without using a reducer. A gas generator includes a compressor that generates compressed air, a burner that burns a fuel mixed with the compressed air received from the compressor so as to generate combustion gas, and a high-pressure turbine that is rotationally driven by the combustion gas received from the burner and generates driving force for the compressor. An output turbine includes a low-pressure turbine that is driven by exhaust gas received from the high-pressure turbine and a power generator that is driven by the low-pressure turbine. A control device reduces opening degree of IGV of the compressor and thereby reduces power of the compressor, and the rotational frequency of the gas generator is increased in a full-speed no-load operating state of the power generator.

Abstract: A method of controlling a supply of a fuel to a combustor of a gas turbine having a compressor upstream of the combustor is provided. The method includes: supplying the fuel to the combustor; obtaining a property value of at least one physical property (PT8, PT7, Tinlet, THBOV) of air used for burning the fuel in the combustor; estimating a heat input (HIengmodel) of the fuel supplied to the combustor based on the property value; measuring a Caloric Value (LCVmea) of the fuel upstream of the combustor; adjusting the estimated heat input (HIengmodel) based on the measured Caloric Value (LCVmea); and controlling a fuel valve regulating the supply of the fuel to the combustor based on the adjusted estimated heat input (HIexpected) and a demanded heat input (FFDEM).

Abstract: Methods and systems are provided for automatically tuning a combustor of a gas turbine engine during a transient period, such as when a state of the gas turbine engine is changing. Once it has been determined whether the state of the gas turbine engine is changing, it is then determined whether a lean blowout is imminent, which is based conditions being monitored. A stability bias is applied to the system if either the state is changing or if lean blowout is imminent until the lean blowout is no longer determined to be imminent. The stability bias monitors operating conditions of the gas turbine engine and determines when one of the operating conditions has overcome a threshold value. Once a threshold value is overcome, a fuel flow fraction is adjusted by a predefined increment. The application of the stability bias is gradually terminated once it is determined that the lean blowout is no longer imminent.

Abstract: The invention relates to a device for controlling an auxiliary engine (8) comprising a gas generator and a free turbine suitable for being able to be connected mechanically to the rotor (12) of a helicopter in order to supply it with thrust power, characterised in that said control device comprises a proportional-integral controller (30) having a proportional gain (Kp) and an integral gain (Ki), which are dependent on the rotation speed of said gas generator, said controller (30) being configured to receive an error signal representing a speed error of said free turbine, and to generate a signal (Sc) for correcting the drive speed of said gas generator obtained by adding a signal proportional to said error signal in accordance with said proportional gain (Kp), and an integrated signal (Si) resulting from the addition of a signal proportional to said error signal in accordance with said integral gain (Ki) and a memory signal (Sm), supplied by a feedback loop (31) of said integrated signal (Si), said memory sig

Abstract: A control system for a combustor system including a plurality of can combustors, each can combustor accommodating combustion of a plurality of combustion fluids in a combustion chamber thereof is provided. The control system may include a calculator calculating: a) a pressure drop for each respective can combustor of the plurality of can combustors between a selected combustion fluid upstream of the combustion chamber and a combustion flow within the combustion chamber of the respective can combustor, and b) a differential between the respective pressure drop for each of the plurality of can combustors and an average pressure drop across all of the plurality of can combustors. The differentials identify can-to-can variation. A controller can modify a combustion parameter of at least one can combustor to reduce the differential for the at least one can combustor. The system can work iteratively to reduce can-to-can variation.

Abstract: A gas turbine fuel supply method and arrangement is provided. The method of controlling a supply of a fuel to a combustor of a gas turbine having a compressor upstream of the combustor, the method including: supplying the fuel to the combustor; obtaining an inlet air pressure (PT7) at a compressor inlet; obtaining an inlet air temperature (Tinlet) at the compressor inlet; obtaining an outlet air pressure (PT8) at a compressor outlet; estimating a heat input (HIengmodel, HIexpected) of the fuel supplied to the combustor based on the inlet air pressure (PT7), the inlet air temperature (Tinlet) and the outlet air pressure (PT8); comparing the estimated heat input (HIengmodel, HIexpected) with a demanded heat input (FFDEM) to derive an error signal; and controlling a fuel valve regulating the supply of the fuel to the combustor based on the error signal.

Abstract: A method for controlling a position actuation system component in a gas turbine engine based on a modified proportional and integral control loop is provided. The method includes determining an error value between a demand signal for the position actuation system component and a position signal for the position actuation system component. The method also includes determining an integral gain scaler as a function of a scheduling parameter value and determining an integral gain based on the determined error value and the determined integral gain scaler. Additionally the method includes determining a proportional gain scaler as a function of the scheduling parameter value and determining a proportional gain based on the determined error value and the determined proportional portion gain scaler. The method adds the determined integral gain with the determined proportional gain to determine a null current value for the position actuation system component.

Abstract: A control system and method for a gas turbine engine are provided A controller (40) is responsive to at least one parameter to control an air-to-fuel ratio. The parameter may be a measured engine exhaust temperature from a temperature sensor (42). During a transient, such as a ramping condition of the engine, a measured value of such parameter may have a time lag affecting one or more control settings during the transient condition. The controller is programmed to predictively determine a bias for the measured value of the parameter to correct such control settings and avoid combustion instabilities and high emissions during such transient conditions.