Abstract: A combined cycle power plant comprises a gas turbine engine comprising a compressor to produce compressed gas, a combustor to produce combustion gas from compressed gas and fuel, and a turbine to receive combustion gas to produce rotational shaft power; a steam system generates steam from water using the combustion gas exiting the turbine; a first stage fuel-gas heater receives the fuel before entering the combustor and receive feedwater from the steam system to transfer heat from the feedwater to the fuel; and a second stage fuel-gas heater receives at least a portion of the fuel from the first stage fuel-gas heater to transfer heat to the fuel from a heat transfer medium before the fuel enters the combustor. A method comprises operating a gas turbine engine, operating a steam cycle, extracting compressed air for cooling the gas turbine engine, and transferring heat to fuel from the compressed air.

Abstract: Embodiments of the invention can provide systems and methods for adjusting clearances in a turbine. According to one embodiment of the invention, there is disclosed a turbine system. The system may include one or more turbine blades; a turbine casing encompassing the one or more turbine blades; and a thermoelectric element disposed at least partially about the turbine casing, wherein the thermoelectric element expands or contracts the turbine casing by heating or cooling at least a portion of the turbine casing, thereby adjusting a clearance between the one or more turbine blades and the turbine casing.

Abstract: Embodiments of the invention can provide systems and methods for condition-based power plant sensor calibration. According to one embodiment of the invention, a system can be provided. The system can include a computer processor. The system can also include a memory operable to store computer-executable instructions operable to: receive data from the one or more power plant sensors; reconcile detected errors within the data from the one or more power plant sensors; calibrate the one or more power plant sensors based at least in part on the detected errors within the data; generate at least one performance model based at least in part on the reconciled data from the one or more power plant sensors; detect anomalies within the at least one performance model; and tune the at least one performance model to account for the anomalies.

Abstract: An embodiment of the present invention has the technical effect of controlling an air preheating system integrated with a gas turbine. The present invention may offer the benefit of extending a turndown range by beating the air (hereinafter “inlet-air”) entering the compressor of the gas turbine. The present invention may also offer the benefit of increasing an efficiency of the powerplant.

Abstract: Embodiments of the invention can provide systems and methods for adjusting clearances in a turbine. According to one embodiment of the invention, there is disclosed a turbine system. The system may include one or more turbine blades; a turbine casing encompassing the one or more turbine blades; and a thermoelectric element disposed at least partially about the turbine casing, wherein the thermoelectric element expands or contracts the turbine casing by heating or cooling at least a portion of the turbine casing, thereby adjusting a clearance between the one or more turbine blades and the turbine casing.

Abstract: Embodiments of the invention can provide systems and methods for condition-based power plant sensor calibration. According to one embodiment of the invention, a system can be provided. The system can include a computer processor. The system can also include a memory operable to store computer-executable instructions operable to: receive data from the one or more power plant sensors; reconcile detected errors within the data from the one or more power plant sensors; calibrate the one or more power plant sensors based at least in part on the detected errors within the data; generate at least one performance model based at least in part on the reconciled data from the one or more power plant sensors; detect anomalies within the at least one performance model; and tune the at least one performance model to account for the anomalies.

Abstract: A lubricating oil varnish mitigation system for a turbine engine. The lubricating oil varnish mitigation system may include a lubricating oil circuit with a lubricating oil therein and a hydraulic oil circuit separate from the lubricating oil circuit with a hydraulic oil therein.

Abstract: Certain embodiments of the invention may include systems, methods, and apparatus for controlling turbine steam output. According to an example embodiment of the invention, a method is provided for controlling steam turbine output. The method can include measuring one or more temperatures or back pressures associated with one or more cells associated with a turbine cooling condenser and controlling temperature distribution of the one or more cells in response, at least in part, to the measured one or more temperatures or back pressures.

Abstract: The present application provides a lubricating oil varnish mitigation system for a turbine engine. The lubricating oil varnish mitigation system may include a lubricating oil circuit with a lubricating oil therein and a hydraulic oil circuit separate from the lubricating oil circuit with a hydraulic oil therein.

Abstract: An embodiment of the present invention has the technical effect of controlling an air preheating system integrated with a gas turbine. The present invention may offer the benefit of extending a turndown range by beating the air (hereinafter “inlet-air”) entering the compressor of the gas turbine. The present invention may also offer the benefit of increasing an efficiency of the powerplant.

Abstract: A system for heating the inlet-air of a gas turbine is provided. The system may incorporate an external energy source to increase the temperature of the inlet-air. The system may extend the turndown of a gas turbine operating at partload.