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: A method detection of leakage through at least one first valve includes admitting an amount of fluid into a first control volume in operable communication with the at least one first valve, thereby pressurizing the first control volume. The first control volume is isolated and a rate of change of pressure in a second control volume in operable communication with the at least one first valve is measured. A system for detecting leakage across at least one first valve includes a first control volume receptive of an amount of fluid and a second control volume in flow communication with the first control volume. At least one first valve is located between the first control volume and the second control volume, and a rate of change in pressure in the second control volume indicates a rate of leakage through the at least one first valve.

Abstract: Methods and systems for operating a gas turbine engine system are provided. The system includes a gas turbine engine that includes at least one combustor configured to receive a flow of fuel from a flow control device and a fuel control system. The fuel control system includes a piping system configured to channel the flow of fuel from a fuel source to the flow control device, a sensor configured to generate a signal indicative of a property of the flow of fuel wherein the property of the flow of fuel is variable over time, and a controller including a processor. The processor is programmed to receive the generated signal, using a flow model of the piping system and the received signal, iteratively track the progress of a plurality of discrete volumes flowing through the piping system, and control the flow of fuel using the flow control devices.

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: A method for transient fuel control for fuel delivery circuits for a plurality of connected gas turbines, the method includes: detecting a transient grid event based on an indication of at least one of a rapid change in a fuel command to the gas turbine or an acceleration of the turbine shaft; upon detection of the transient grid event, commanding a gas turbine controller to transfer the gas turbine to at least one intermediate load; adjusting a fuel split to maintain combustor stability during the transient grid event, and using a predetermined island load demand signal to apportion an island load demand among the connected gas turbine generators.

Abstract: A method for transient fuel control for fuel delivery circuits for a plurality of connected gas turbines, the method includes: detecting a transient grid event based on an indication of at least one of a rapid change in a fuel command to the gas turbine or an acceleration of the turbine shaft; upon detection of the transient grid event, commanding a gas turbine controller to transfer the gas turbine to at least one intermediate load; adjusting a fuel split to maintain combustor stability during the transient grid event, and using a predetermined island load demand signal to apportion an island load demand among the connected gas turbine generators.