Abstract: A combined cycle power plant that includes a first gas turbine engine including a first turbine section, a second gas turbine engine including a second turbine section having an aft outlet configured to discharge an exhaust gas stream, an emissions reduction system configured to receive the exhaust gas stream discharged from the second gas turbine engine, and configured to remove oxides of nitrogen from the exhaust gas stream, and an interstage extraction system communicatively coupled with the first turbine section. The interstage extraction system is configured to selectively extract turbine extraction air from the first turbine section for providing heat to the emissions reduction system.

Abstract: A combined cycle power plant that includes a first gas turbine engine including a first turbine section, a second gas turbine engine including a second turbine section having an aft outlet configured to discharge an exhaust gas stream, an emissions reduction system configured to receive the exhaust gas stream discharged from the second gas turbine engine, and configured to remove oxides of nitrogen from the exhaust gas stream, and an interstage extraction system communicatively coupled with the first turbine section. The interstage extraction system is configured to selectively extract turbine extraction air from the first turbine section for providing heat to the emissions reduction system.

Abstract: Systems and methods for preheating fuel in a gas turbine engine are provided. In one embodiment, a system may include a gas turbine engine, a fuel line in fluid communication with the gas turbine engine, a gas turbine compartment disposed about the gas turbine engine, and a first conduit in fluid communication with the gas turbine compartment. The first conduit may include ventilation discharge air from the gas turbine compartment. The system also may include a first heat exchanger in communication with the fuel line and the first conduit. The first heat exchanger may be configured to exchange heat between the fuel and the ventilation discharge air from the gas turbine compartment.

Abstract: Embodiments of systems and methods described in this disclosure are directed to operating a combined cycle power plant. In certain embodiments, systems and methods can be provided for a combined cycle power plant incorporating a control system that uses a holistic approach to continuously and automatically adjust a heat rate of the combined cycle power plant and achieve a desired efficiency. In accordance with one embodiment of the disclosure, the control system can be used to dynamically control various operations of the combined cycle power plant, including addressing of certain conflicting requirements such as avoiding generation of superheated steam in an attemperator while concurrently maintaining exhaust emissions within allowable regulatory limits and maintaining exhaust gas temperatures within allowable material capability limits.

Abstract: Systems and methods for utilizing gas turbine compartment ventilation discharge air. In one embodiment, a system may include a gas turbine engine having a compressor. The system also may include a gas turbine compartment disposed about the gas turbine engine. Moreover, the system may include an inlet bleed heat (IBH) manifold in fluid communication with the compressor. The gas turbine compartment may be in fluid communication with the IBH manifold for providing the IBH manifold with ventilation discharge air from the gas turbine compartment.

Abstract: Systems and methods to control performance via control of compressor operating limit line (OLL) protection actions. According to an embodiment of the disclosure, a method of controlling a turbine in a power plant can be provided. The method may include receiving a selection of a desired performance parameter associated with an operational mode of a power plant; receiving a set of measured performance parameters at a current operating condition of a turbine associated with the power plant; receiving an operating limit line (OLL) of a compressor associated with the turbine; and receiving a compressor pressure ratio (CPR) at the current operating condition of the turbine.

Abstract: A gas turbine system includes a compressor protection subsystem; a hibernation mode subsystem; and a control subsystem that controls the compressor subsystem and the hibernation subsystem. At partial loads on the turbine system, the compressor protection subsystem maintains an air flow through a compressor at an airflow coefficient for the partial load above a minimum flow rate coefficient where aeromechanical stresses occur in the compressor. The air fuel ratio in a combustor is maintained where exhaust gas emission components from the turbine are maintained below a predetermined component emission level while operating at partial loads.

Abstract: Systems and methods for utilizing gas turbine compartment ventilation discharge air. In one embodiment, a system may include a gas turbine engine having a compressor. The system also may include a gas turbine compartment disposed about the gas turbine engine. Moreover, the system may include an inlet bleed heat (IBH) manifold in fluid communication with the compressor. The gas turbine compartment may be in fluid communication with the IBH manifold for providing the IBH manifold with ventilation discharge air from the gas turbine compartment.

Abstract: Systems and methods for preheating fuel in a gas turbine engine are provided. In one embodiment, a system may include a gas turbine engine, a fuel line in fluid communication with the gas turbine engine, a gas turbine compartment disposed about the gas turbine engine, and a first conduit in fluid communication with the gas turbine compartment. The first conduit may include ventilation discharge air from the gas turbine compartment. The system also may include a first heat exchanger in communication with the fuel line and the first conduit. The first heat exchanger may be configured to exchange heat between the fuel and the ventilation discharge air from the gas turbine compartment.

Abstract: Systems and methods for de-icing an inlet screen and dehumidifying an inlet air filter in a gas turbine engine are disclosed herein. In one embodiment, a method may include determining a current inlet screen temperature. The method also may include determining a desired inlet screen temperature. If the current inlet screen temperature is less than the desired inlet screen temperature, the method may further include determining a first amount of gas turbine compartment ventilation discharge air necessary to achieve the desired inlet screen temperature, extracting the first amount of gas turbine compartment ventilation discharge air, and conveying the first amount of gas turbine compartment ventilation discharge air to the inlet screen.

Abstract: A gas turbine system includes a compressor protection subsystem; a hibernation mode subsystem; and a control subsystem that controls the compressor subsystem and the hibernation subsystem. At partial loads on the turbine system, the compressor protection subsystem maintains an air flow through a compressor at an airflow coefficient for the partial load above a minimum flow rate coefficient where aeromechanical stresses occur in the compressor. The air fuel ratio in a combustor is maintained where exhaust gas emission components from the turbine are maintained below a predetermined component emission level while operating at partial loads.