Abstract: An internal combustion engine in which the power output is controlled by modulating at least one of the compression ratio, expansion ratio, ratio of expansion rate to compression rate, air to fuel ratio, and steam to air ratio. Continuous isobaric catalytic combustion followed by isothermal expansion and the use of separate compressor and expander devices are used. Control dynamically maximizes fuel efficiency for the given power demand conditions. Power output is controlled by modulating flame temperature and/or pressure instead of by throttling. Lean combustion, high compression ratio, exhaust heat recuperation, and high power density and fuel economy are provided. External cooling is minimized or eliminated. Insulation of the engine effectively reduces energy losses to friction. Interchangeable use of gasoline, hydrogen and ammonia at high fuel efficiency is made possible for transitional periods of fuel availabilities. An injector suitable for isothermal expansion is provided.

Abstract: A method for assembling a gas turbine engine is described. The method includes coupling a first fuel system interface (FSI-1) to a second fuel system interface (FSI-2), and coupling one of the FSI-1 and the FSI-2 to the engine. The method includes coupling a first control system and a second control system to the FSI-1 and to the FSI-2. The first control system includes a first driver A and a second driver A, and the second control system includes a first driver B and a second driver B. The method includes configuring the first control system and the second control system to apply a first over-speed logic algorithm and a second over-speed logic algorithm to determine operation of the first driver A, the second driver A, the first driver B, and the second driver B.

Abstract: Position sensors, metering valve assemblies, and fuel delivery and control systems are provided. In an embodiment, by way of example only, a position sensor includes a rotor, a primary winding wound around the rotor, a stator surrounding at least a portion of the rotor and the primary winding, and a secondary winding disposed adjacent to the stator. At least one of the primary winding and the secondary winding comprises copper and nickel.

Abstract: A method of actively controlling pattern factor in a gas turbine engine includes the steps of issuing fuel into a combustion chamber of a gas turbine engine through one or more circumferentially disposed fuel injectors, determining an initial circumferential pattern factor in the combustion chamber, and adjusting fuel flow through one or more selected fuel injectors based on the initial circumferential pattern factor, to yield a modified circumferential pattern factor in the combustion chamber. The step of determining the circumferential pattern factor can include the steps of detecting a chemiluminescent signature within the combustor, correlating the chemiluminescent signature to an equivalence ratio, and computing the initial circumferential pattern factor based on the equivalence ratio.

Abstract: Certain embodiments of the invention may include systems and methods for compensating fuel composition variations in a gas turbine. According to an example embodiment of the invention, a method is provided for compensating for fuel composition variations in a turbine. The method can include: monitoring at least one fuel parameter associated with a turbine combustor; monitoring one or more combustion dynamics characteristics associated with the turbine combustor; monitoring one or more performance and emissions characteristics associated with the turbine; estimating fuel composition based at least in part on the at least one fuel parameter, the one or more combustion dynamics characteristics, and the one or more performance and emissions characteristics, and adjusting at least one fuel parameter based at least in part on the estimated fuel composition.

Abstract: A fuel delivery and control system is provided including a dual pump fluid circuit configuration comprising a fixed positive displacement pump sized to supply the main engine burn flow ranging from above windmill through cruise and a variable displacement pump sized to supply fluid to engine actuators, valves and other hydraulically operated engine components with a pump flow sharing system interconnecting the two pumps. The combined flow from the two pumps is sufficient to meet the engine flow demand for windmill relight and maximum flow conditions. During cruise or normal operating conditions, the pumps operate in completely isolated flow circuits, minimizing recirculation and therefore heat input into the fuel supply system.

Abstract: Fuel control arrangements provide and control fuel flow to injectors through fuel control valves. The injectors are connected to respective fuel control valves which in turn are connected to a first fuel flow path. The injectors are also connected to a second fuel flow path. The fuel paths are associated with a fuel source and generally have a recirculation valve between them. When flow in the flow path is stopped, recirculation of fuel can be provided across the recirculation valve to prevent fuel degradation. By provision of a restrictor valve in the second fuel flow path control of fuel recirculation can be achieved, as well as greater flexibility by presenting fuel flow separately through the second flow path to the injector whilst the first flow path is inhibited.

Abstract: An internal combustion engine in which the power output is controlled by modulating at least one of the compression ratio, expansion ratio, ratio of expansion rate to compression rate, air to fuel ratio, and steam to air ratio. Continuous isobaric catalytic combustion followed by isothermal expansion and the use of separate compressor and expander devices are used. Control dynamically maximizes fuel efficiency for the given power demand conditions. Power output is controlled by modulating flame temperature and/or pressure instead of by throttling. Lean combustion, high compression ratio, exhaust heat recuperation, and high power density and fuel economy are provided. External cooling is minimized or eliminated. Insulation of the engine effectively reduces energy losses to friction. Interchangeable use of gasoline, hydrogen and ammonia at high fuel efficiency is made possible for transitional periods of fuel availabilities. An injector suitable for isothermal expansion is provided.

Abstract: A method of operating an electronic engine control to compensate for speed changes. The method includes receiving a fuel flow request, sensing actual engine rotor speed, calculating a fuel flow correction factor, establishing a final fuel flow request based on the fuel flow correction factor, and adjusting the actual set point of the MV to compensate for the actual engine rotor speed.

Abstract: A fuel-injection device in a turbomachine is disclosed. The device includes a high-pressure pump supplying a flow control valve, whose outlet is connected via a pressurization and cut-off valve to a fuel-injector feed pipe. The valve is connected to the inlet and to the outlet of the pump in order to define two fuel pressurization thresholds, one of which is used to start-up and restart the turbomachine and the other is used for operating the turbomachine from an idle speed and for commanding an equipment with variable geometry.

Abstract: In a testing overspeed protection system: a) on receiving an order to start a turbomachine, an electronic regulation system (ERS) of the turbomachine sends an order to a control circuit of a fuel cutoff member to close the fuel cutoff member or to keep it in the closed position; b) the closed state of the FCM is verified on the basis of information transmitted to the ERS and representative of the position of the FCM; c) if the result of the verification in b) is positive, the ERS sends an order to the FCM control circuit to authorize opening of the FCM and enable the starting procedure to continue; and d) if the result of the verification in b) is negative, the ERS issues fault information concerning the overspeed protection system.

Abstract: In operating a gas turbine, there can be a difference between the desired heating value of the fuel and the actual needs of the fuel for the supplied fuel to be ignited. In one aspect, fuel parameters related to the molecular weight of the fuel such as specific gravity and pressure drop are determined. Ignitability of the fuel is calculated based on the fuel parameters and adjusted as necessary to bring the fuel's ignitability to designed values. The fuel's ignitability can be calculated without actually igniting the fuel and also without direct knowledge of the fuel's calorific value or its composition.

Abstract: A method and algorithm are provided to operate a gas turbine at baseload in an emission compliant capable mode to avoid combustion dynamics while operating with cold fuel and hot fuel combustion hardware. The method includes performing a gas turbine operational sequence such as a startup to an emission compliant capable mode. A gas fuel temperature is measured. The gas turbine is operated in the emissions compliant capable mode according to a designated fuel split for avoiding combustion dynamics when a temperature for a gas fuel is below a designated value. A determination is made whether a modified wobbe index for the gas fuel is below an emissions compliant value. An alarm is activated if the modified wobbe index is below the emissions compliant value to notify the operator of a potential emissions shift.

Abstract: A gas turbine engine fuel control system is provided that includes a fuel metering valve and a thrust control valve. The fuel metering valve includes a metering valve inlet and a metering valve outlet. The metering valve inlet is adapted to receive a flow of fuel, and is configured to control the flow of fuel through the metering valve outlet. The thrust control valve is adapted to receive thrust control valve override signals and is configured, in response thereto, to move from a first position, in which flow from the metering valve is not impacted, and a second position, in which flow from the metering valve is blocked while flow through a fixed-area orifice is allowed.

Abstract: A method of operating a gas turbine engine having a turbine and a compressor connected via a shaft, a main fuel supply line for supplying fuel to a combustor that is positioned to release expanding hot gases to the turbine, the engine further including a starter/generator connected to the shaft via a gearbox assembly, the method is characterised the step of during engine start up fuel is circulated in a re-circulating fuel circuit positioned on the main fuel supply line and which has a first fuel/oil heat exchanger, for cooling the oil, and a fuel accumulator.

Abstract: A turbine engine fuel supply system includes a priority flow line, a plurality of secondary fuel loads, an electric fuel metering pump, and a mechanically-driven fuel pump. The priority flow line is used to supply fuel to one or more gas turbine engine fuel manifolds. The electric fuel metering pump has a fuel inlet and a fuel outlet, and is adapted to be selectively energized and, upon being energized, to draw fuel into its fuel inlet and discharge the fuel from its fuel outlet for supply to the priority flow line. The mechanically-driven fuel pump has a fuel inlet, and a fuel outlet that is in fluid communication with the electric fuel metering pump fuel inlet and the plurality of secondary fuel loads. As such, fuel may be supplied to the secondary fuel loads independent of the electric fuel metering pump, which advantageously reduces the electrical power consumption of the electric fuel metering pump.

Abstract: A system and method is provided for controlling a variable displacement piston pump that supplies fluid to one or more loads. If fluid is being supplied through a metering valve to a load, then the variable displacement piston pump is controlled to operate in accordance with a variable flow/variable discharge pressure scheme. However, if fluid is not being supplied through the metering valve to the load, then the variable displacement piston pump is controlled to operate in accordance with a variable flow/constant discharge pressure scheme.

Abstract: A method and system are disclosed that enable an automatic regulation of a vanadium inhibitor in a fuel of a gas turbine. In one embodiment, the method includes obtaining an indication as to whether an additional inhibitor is required in the fuel of the gas turbine based on an amount of vanadium and an inhibitor in the fuel of the gas turbine, in response to the indication that the additional inhibitor is required, having an inhibitor control system automatically instructing an injector to inject the additional inhibitor into the fuel of the gas turbine to inhibit the vanadium.

Abstract: Methods and systems for delivering fuel in a gas turbine engine are provided. The system includes a plurality of can annular combustors that includes at least a first set of combustors of the plurality of can annular combustors and at least a second set of combustors of the plurality of can annular combustors wherein each set of combustors is supplied by a separately controllable respective fuel delivery system. The method includes supplying fuel at a first fuel schedule to the first set of combustors and supplying fuel at a second fuel schedule to the second set of combustors during a first mode of operation wherein the second fuel schedule is different than the first fuel schedule, and supplying fuel at the second fuel schedule to the first and second sets of combustors during a second mode of operation.

Abstract: In operating a gas turbine, there can be a difference between the desired heating value of the fuel and the actual needs of the fuel for sustainable combustion during various stages of the turbine operation. In one aspect, combustible lean limit operation of the gas turbine free of lean blow out is enabled by adjusting fuel-air-ratio of the fuel and fuel-air mixture properties, based on the operation requirements of the turbine and flammability of the fuel components.

Abstract: The fuel system of a dual fuel turbine includes a flow control valve having a metering purge valve that in one state directly meters fuel to injectors of the turbine, in another state closes of fuel flow and passes purge air to the injectors and in another state positively closes of flow of both fuel and purge air. The metering purge valve is a pressure compensated spool valve that has a unique cross-ported interchange that passes fuel from the inlet through the spool to the metering edge. The direct metering of the valve to the injectors eliminates the need for additional shut off valves, and if used with a combining valve having an integral distributor section metering fuel to multiple injectors, the need for a separate flow divider is also eliminated. The valve can be actively cooled by dedicated coolant lines or lines shared with other flow control components such as additional metering valves for either the primary or secondary fuel.

Abstract: The present invention improves the reliability of a combusting system including multiple combustors and improves an environmental performance thereof. The invention includes a device that delays the start time of fuel injection from a fuel nozzle of a combustor including a ignitor from the start time of fuel injection from a fuel nozzle of the combustor not including the ignitor.

Abstract: The present invention provides a plasma arc torch that can be used for lean combustion. The plasma arc torch includes a cylindrical vessel, an electrode housing connected to the first end of the cylindrical vessel such that a first electrode is (a) aligned with a longitudinal axis of the cylindrical vessel, (b) extends into the cylindrical vessel, and (c) can be moved along the longitudinal axis, a linear actuator connected to the first electrode to adjust a position of the first electrode, a hollow electrode nozzle connected to the second end of the cylindrical vessel such that the center line of the hollow electrode nozzle is aligned with the longitudinal axis of the cylindrical vessel, and wherein the tangential inlet and the tangential outlet create a vortex within the cylindrical vessel, and the first electrode and the hollow electrode nozzle creates a plasma that discharges through the hollow electrode nozzle.

Abstract: A method for adjusting fuel flow to individual combustion chambers in a gas turbine having fuel nozzles for each combustion chamber, manifolds for supplying fuel to at least one fuel nozzle in each combustion chamber, wherein the manifolds have flow metering devices for the fuel nozzles and a controller for adjusting the flow metering devices, the method including: supplying fuel to the combustion chambers through at least one of the manifolds; combusting the fuel in the combustion chambers and generating exhaust gases which drive the gas turbine; determining whether one of the combustion chambers is operating relatively lean or rich by actuating a corresponding to the one of the combustion chambers to adjust fuel flowing to the one of the combustion chambers; sensing a condition of the exhaust gases at various exhaust regions in the exhaust gases and determining a change in the condition of the exhaust gas due to the actuation of the flow metering device, and correlating the change in the sensed condition of

Abstract: System, methods and apparatus for dynamic control of mixing of diluent and fuel at desired diluent-to-fuel ratios to obtain low level of undesirable emissions in a combustion system are described.

Abstract: In a turbine engine hydrogen is injected into the combustor in response to a power output level of the turbine engine. In a preferred embodiment, gaseous hydrogen is always injected at low-power operations and switched off at mid-power and high-power operations.

Abstract: Methods and systems for controlling a dynamic response in a gas turbine fuel control system are provided. The control system includes a component model adapted to regulate a fuel supply pressure for a gas turbine, a pressure sensor adapted to sense a pressure of fuel supplied to the gas turbine, and a feedback module including integral plus state feedback, the feedback module adapted to provide a positive feedback reference signal to the component model such that a response time of the gas turbine fuel control system to changes in fuel pressure is facilitated being reduced.

Abstract: Tuning processes implemented by an auto-tune controller are provided for measuring and adjusting the combustion dynamics and the emission composition of a gas turbine (GT) engine via a tuning process. Initially, the tuning process includes monitoring parameters, such as combustion dynamics and emission composition. Upon determining that one or more of the monitored parameters exceed a critical value, these “out-of-tune” parameters are compared to a scanning order table. Upon comparison, the first out-of-tune parameter that is matched within the scanning order table is addressed. The first out-of-tune parameter is then plotted as overlaid slopes on respective graphs, where the graph represents a fuel-flow split. Typically, the slopes are plotted as a particular out-of-tune parameter against a particular fuel-flow split. The slopes for each graph are considered together by taking into account the combined impact on each out-of-tune parameter when a fuel-flow split is selected for adjustment.

Abstract: A gas turbine combustor includes a combustion chamber defined by a combustor liner, the combustor liner having an upstream end cover supporting one or more nozzles arranged to supply fuel to the combustion chamber where the fuel mixes with air supplied from a compressor. A transition duct is connected between an aft end of the combustion chamber liner and a first stage turbine casing, the transition duct supplying gaseous products of combustion to the first stage turbine nozzle. One or more additional fuel injection nozzles are arranged at an aft end of the transition duct for introducing additional fuel into the transition duct upstream of the first stage turbine nozzle.

Abstract: An example fuel system includes a fuel sensor configured to sense at least one characteristic of a fuel provided to an engine. The fuel is selected from a plurality of different fuel types. The fuel system also includes a controller that is configured to meter the fuel in response to the at least one characteristic of the fuel.

Abstract: Disclosed is a fuel injector for a gas turbine engine combustor that includes a fuel nozzle for injecting fuel into the gas turbine engine combustor and a fiber optic microphone operatively associated with the fuel nozzle for measuring acoustic pressure differentials within a combustion chamber of the gas turbine engine combustor. The fiber optic microphone includes a fiber bundle having at least one light transmitting fiber and one light receiving fiber; and a dynamic pressure-sensing diaphragm operatively spaced apart from a sensing end of the fiber bundle. The diaphragm has a reflective surface and is formed from a material capable of withstanding temperatures associated with flame exposure. The diaphragm is adapted and configured for deflecting in response to acoustic pressure changes within the combustion chamber.

Abstract: An electronic control apparatus which is applied to a gas turbine is provided. The electronic control apparatus includes a cylindrical combustor in which air compressed by a compressor is supplied, a plurality of fuel injection valves aligned in a circumferential direction in the combustor which are capable of injecting fuel into the combustor, and an ignition plug provided in the combustor which is capable of igniting a fuel-air mixture within the combustor. The electronic control apparatus controls the operation of the plurality of fuel injection valves so that when the gas turbine is started up, fuel injection opening times of the #6 and #12 fuel injection valves which are positioned far from the ignition plug are later than fuel injection opening times of the #1 and #7 fuel injection valves which are positioned close to the ignition plug.

Abstract: A combustion control system for a turbine engine is disclosed. The combustion control system includes a fuel injector having a main fuel supply and pilot fuel supply coupled to a combustor of the turbine engine. The combustion control system also includes a sensor coupled to a transfer tube. The transfer tube is fluidly coupled to the combustor, and the sensor is configured to detect a pressure pulse in the combustor. A semi-infinite coil is also coupled to the transfer tube. The combustion control system also includes a controller electrically connected to the sensor. The controller is configured to compare an amplitude of the pressure pulse within a frequency range to a threshold amplitude, and adjust the pilot fuel supply in response to the comparison.

Abstract: A system and method for modifying the supply of fuel to injectors to attenuate combustion oscillations in a gas turbine engine. The gas turbine engine may comprise a combustor, a plurality of injectors and a manifold. The plurality of injectors may be operable to provide fuel to the combustor. The manifold may be configured to supply fuel to all of the plurality of injectors or to only a portion of the plurality of injectors in reaction to a determination of an existence of combustion oscillations.

Abstract: A fuel controller for a combustion system in a gas turbine having a combustion system, a fuel supply, a pressure control valve proximate the combustion system and a first pressure sensor proximate the pressure control valve, the fuel controller including: a proportional-integrated (PI) logic unit generating a control command for the pressure control valve and receiving input signals representing a desired fuel pressure at the pressure control valve and an input signal from the first pressure sensor representing an actual fuel pressure at the pressure control valve, and a plurality of control gains stored in electronic memory of the controller, wherein each control gain is applicable to a predefined operating condition of the gas turbine, and wherein the controller determines which set of control gains is to be applied by the PI logic unit based on an actual operating condition of the gas turbine.

Abstract: An apparatus for actively controlling fuel flow from a fuel pump to a mixer assembly of a gas turbine engine combustor, where the mixer assembly includes a pilot mixer and a main mixer. The pilot mixer further includes an annular pilot housing having a hollow interior, a primary fuel injector mounted in the pilot housing and adapted for dispensing droplets of fuel to the hollow interior of the pilot housing, a plurality of axial swirlers positioned upstream from the primary fuel injector. The fuel flow control apparatus further includes: at least one sensor for detecting dynamic pressure in the combustor; a fuel nozzle; and, a system for controlling fuel flow supplied by the fuel nozzle through the valves. The fuel nozzle includes: a feed strip with a plurality of circuits for providing fuel to the pilot mixer and the main mixer; and, a plurality of valves associated with the fuel nozzle and in flow communication with the feed strip thereof.

Abstract: A method and controller for identifying lean blowout conditions in a Dry Low NOx (DLN) combustor during a premix mode. An effective approach to quickly and reliably identify a blowout during operation in the premix mode is by the effect on fuel normalized power (FNP). FNP is a useful signal, in that a power reduction from a blowout may be distinguished much slower changes in power resulting from global fuel demand (changing load request). A difference between the FNP and a filtered FNP parameter may be compared against a predetermined threshold. If the difference exceeds the threshold, a lean blowout is identified and a signal may be transmitted to the turbine controller to reposition combustor operation away from blowout conditions.

Abstract: Apparatus for regulating the flow rate of fuel to a turboshaft engine in acceleration or in deceleration, the engine having a free turbine and a core engine, the apparatus comprising sensors transmitting information to regulator means, said information relating: to a first speed of rotation NTL of said free turbine; to a second speed of rotation Ng of said engine's gas generator; to an internal temperature T4 of the gas at the inlet to the free turbine; to the external pressure; and to the external temperature. The apparatus further comprises control means activated by said regulator means to actuate a fuel metering system of the engine. In addition, the regulator means evaluates the flow rate of fuel to be supplied to the engine in acceleration or in deceleration on the basis of at least one optimum regulation relationship, said regulation relationship determining a main modulated flow rate as a function of a modulated speed of rotation.

Abstract: A system is provided and includes first and second water supplies at first and second relatively high and low temperatures, respectively, a heat exchanger, coupled to the water supplies, through which fuel and relative amounts of the water supplies at the first and second temperatures flow for fuel heating and a controller, operably interposed between the water supplies and the heat exchanger, to select and/or modulate the relative amounts of the water supplies permitted to flow through the heat exchanger to heat the fuel to a temperature based on a heating requirement to meet a modified wobbe index (MWI) rating.

Abstract: A gas turbine engine control system includes a module operable to fail-fix the gas turbine engine to one of a multiple of pre-determined modes in response to failure of an automatic control.

Abstract: A fuel control assembly for use in a gas turbine engine. The fuel control assembly includes a first trip device configured to selectively release a fluid pressure from a trip fluid system. At least one gas fuel control valve is coupled to the first trip device. The gas fuel control valve includes a second trip device for moving the gas fuel control valve to a safe position during a purge air operation.

Abstract: Systems and methods for controlling fuel flow within a machine are provided. A plurality of fuel types provided to the machine and a plurality of fuel circuits associated with the machine may be identified, each of the plurality of fuel circuits adapted to be provided with one or more of the plurality of fuel types. A fuel flow parameter for calculating fuel flow may be identified, and a respective fuel flow for each of the one or more fuel types provided to each of the plurality of fuel circuits may be calculated based at least in part on the identified fuel flow parameter. Based at least in part on the calculation of the respective fuel flows, operation of one or more fuel flow control devices providing fuel to the plurality of fuel circuits may be controlled.

Abstract: A fuel system for a turbine, including a plurality of fuel control valves connected to the turbine and in parallel with each other; and a controller for opening each of the control valves to pass a lower controllable fuel flow through each valve, and for further opening one of the control valves in response to a control signal for controlling the turbine.

Abstract: A system and method provide dual level pressurization control of a fuel supply system based on whether fuel is being supplied to one or more secondary fuel loads. Fuel pump discharge backpressure is maintained above either a first minimum pressure value or a lower second minimum pressure value by determining whether fuel is being supplied to one or more secondary fuel loads. The fuel pump discharge pressure is maintained above the first minimum pressure value if it is determined that fuel is being supplied to the one or more secondary loads. The fuel pump discharge backpressure is maintained above the lower second minimum pressure value if it is determined that fuel is not being supplied to the one or more secondary loads.

Abstract: An Active Combustion Control System and method provides for monitoring combustor pressure and modulating fuel to a gas turbine combustor to prevent combustion dynamics and/or flame extinguishments. The system includes an actuator, wherein the actuator periodically injects pulsed fuel into the combustor. The apparatus also includes a sensor connected to the combustion chamber down stream from an inlet, where the sensor generates a signal detecting the pressure oscillations in the combustor. The apparatus controls the actuator in response to the sensor. The apparatus prompts the actuator to periodically inject pulsed fuel into the combustor at a predetermined sympathetic frequency and magnitude, thereby controlling the amplitude of the pressure oscillations in the combustor by modulating the natural oscillations.

Abstract: Methods and systems for operating a gas turbine engine system are provided. The system includes a fuel control system. The fuel control system includes a plurality of sensors positioned about the gas turbine engine system and configured to measure at least one parameter associated with the sensor, and a processor programmed to receive a signal from at least one of the plurality of sensors indicative of a composition of the fuel. The processor is further programmed to determine the physical properties of a fuel at an inlet to the flow control devices using a flow model and the at least one signal, determine a corresponding correction to a gas fuel flow gain using the determined physical properties, and automatically control fuel delivery as well as fuel split between the fuel injection points on the combustor using the adjusted flow gain to facilitate permitting a relatively large variation in the fuel composition for use in the gas turbine engine.

Abstract: An embodiment of the invention applies a physics based approach to determine the mass flowrate of the fuel required for a robust ignition mode. This approach uses a closed-loop controls methodology. Here, a turbine control system receives a plurality of operating data. The turbine control system utilizes at least one algorithm, which applies an energy balance to the received operating data. The operating data may include, but is not limited to, airflow data, data from the fuel system, data related to the shaft work, exhaust data, and data related to the heat loss. This energy balance is used to determine the required mass flow rate.

Abstract: A trim valve includes a valve housing having an inlet section and an outlet section. A valve shaft is mounted to the valve housing to be stationary with respect thereto. The valve shaft includes an internal flow passage in fluid communication with the outlet section of the valve housing. A valve rotor is disposed inboard of the valve housing and outboard of the valve shaft for modulating flow through the valve housing. The valve rotor is mounted for rotational movement within the valve housing between a fully open position in which a flow path is defined between the inlet and outlet sections of the valve housing, and a reduced flow position in which the valve rotor at least partially blocks the flow path. An actuator is operatively connected to the valve housing to actuate the valve rotor between the fully open and reduced flow positions.

Abstract: Certain embodiments of the invention may include systems and methods for providing unchoked control of gas turbine fuel control valves. According to an exemplary embodiment of the invention, a method is provided for active control of a gas flow control valve. The method may include receiving a desired fuel command and an inlet pressure parameter, and determining a gas flow gain based at least in part on the inlet pressure parameter. The method may also include determining a valve flow coefficient based at least in part on the desired fuel command and the gas flow gain, and controlling the gas flow control valve based at least in part on the valve flow coefficient.

Abstract: Systems and methods for controlling fuel mixing are provided. One or more parameters associated with the operation of a machine configured to receive a combined fuel may be identified. A fuel flow of the combined fuel that is provided to the machine may be determined. Based at least in part on the identified parameters, a ratio of a first fuel type included in the combined fuel to the determined fuel flow may be determined. The first fuel type may have a heating value that is greater than a second fuel type included in the combined fuel. A flow of the first fuel type may be set based at least in part on the ratio. Subsequent to setting the flow of the first fuel type, an energy content of the fuel flow of the combined fuel may be determined, and the flow of the first fuel type may be adjusted based at least in part on the determined energy content.