Abstract: A method for adjusting startup floor pressure levels of HRSG steam circuits is implemented by a pressure controlling computing device including a processor and a memory. The method includes receiving a plurality of measured plant operating values associated with a HRSG steam circuit, identifying a plurality of candidate pressure levels for use in pressurizing the HRSG steam circuit, determining a calculated steam velocity level for each of the plurality of candidate pressure levels, identifying a steam velocity limit for a steam piping section of the HRSG steam circuit, selecting a lowest pressure level of the plurality of candidate pressure levels, wherein the lowest pressure level is associated with a determined calculated steam velocity level that does not exceed the identified velocity limit, and pressurizing the HRSG steam circuit to the selected lowest pressure level.

Abstract: A power generation system may include a generator, and a gas turbine system for powering the generator, the gas turbine system including a turbine component, an integral compressor and a combustor to which air from the integral compressor and fuel are supplied, the combustor arranged to supply hot combustion gases to the turbine component, and the integral compressor having a flow capacity greater than an intake capacity of at least one of the combustor and the turbine component, creating an excess air flow. A turbo-expander may also power the generator. A first control valve control flow of the excess air flow along an excess air flow path to an inlet of the turbo-expander. An educator may be positioned in the excess air flow path for using the excess air flow as a motive force to augment the excess air flow with additional air. A discharge of the turbo-expander is supplied to an inlet of the integral compressor.

Abstract: A power generation system may include: a first gas turbine system including a first turbine component, a first integral compressor and a first combustor to which air from the first integral compressor and fuel are supplied. The first integral compressor has a flow capacity greater than an intake capacity of the first combustor and/or the first turbine component, creating an excess air flow. A second gas turbine system may include similar components to the first except but without excess capacity in its compressor. A turbo-expander may be operatively coupled to the second gas turbine system. Control valves may control flow of the excess air flow from the first gas turbine system to at least one of the second gas turbine system and the turbo-expander, and flow of a discharge of the turbo-expander to an exhaust of at least one of the first turbine component and the second turbine component.

Abstract: A power generation system may include: a first gas turbine system including a first turbine component, a first integral compressor and a first combustor to which air from the first integral compressor and fuel are supplied. The first integral compressor has a flow capacity greater than an intake capacity of the first combustor and/or the first turbine component, creating an excess air flow. A second gas turbine system may include similar components to the first except but without excess capacity in its compressor. A turbo-expander may be operatively coupled to the second gas turbine system. Control valves may control flow of the excess air flow from the first gas turbine system to at least one of the second gas turbine system and the turbo-expander, and flow of a discharge of the turbo-expander to an inlet of at least one of the first integral compressor and the second compressor.

Abstract: A power augmentation system for a gas turbine that is electrically coupled to a power grid incudes, in serial flow order, a compressed air supply, a compressed air storage tank and an expansion turbine that is disposed downstream from the compressed air storage tank. An exhaust outlet of the expansion turbine is in fluid communication with at least one of an inlet section or a compressor of the gas turbine.

Abstract: Various embodiments include a system having: a computing device configured to control a power plant system including a steam turbine (ST), a gas turbine (GT), and a heat recovery steam generator (HRSG) fluidly connected with the ST and the GT, by performing actions including: obtaining data representing a target steam specific enthalpy in a bowl section of the ST; determining a current steam pressure at an outlet of the HRSG and a current steam temperature at the outlet of the HRSG; calculating an actual steam specific enthalpy in the bowl section of the ST based upon the current steam pressure at the outlet of the HRSG and the current steam temperature at the outlet the HRSG; and modifying a temperature of steam entering the ST in response to determining that the calculated actual steam specific enthalpy in the bowl section differs from the target steam specific enthalpy in the bowl section by a threshold.

Abstract: A power augmentation system for a gas turbine that is electrically coupled to a power grid incudes, in serial flow order, a compressed air supply, a compressed air storage tank and an expansion turbine that is disposed downstream from the compressed air storage tank. An exhaust outlet of the expansion turbine is in fluid communication with at least one of an inlet section or a compressor of the gas turbine.

Abstract: A system for heating fuel in a combined cycle gas turbine includes a fuel heat exchanger downstream from a turbine outlet, and the fuel heat exchanger has an exhaust gas inlet, an exhaust gas outlet, a fuel inlet, and a fuel outlet. A first exhaust gas plenum has a first exhaust gas inlet connection between the turbine outlet and a heat exchanger and a first exhaust gas outlet connection upstream from the exhaust gas inlet. A second exhaust gas plenum has a second exhaust gas inlet connection downstream from at least a portion of the heat exchanger and a second exhaust gas outlet connection upstream from the exhaust gas inlet.

Abstract: A power generation system may include a generator, and a gas turbine system for powering the generator, the gas turbine system including a turbine component, an integral compressor and a combustor to which air from the integral compressor and fuel are supplied, the combustor arranged to supply hot combustion gases to the turbine component, and the integral compressor having a flow capacity greater than an intake capacity of at least one of the combustor and the turbine component, creating an excess air flow. A turbo-expander may also power the generator. A first control valve control flow of the excess air flow along an excess air flow path to an inlet of the turbo-expander. An educator may be positioned in the excess air flow path for using the excess air flow as a motive force to augment the excess air flow with additional air. A discharge of the turbo-expander is supplied to an inlet of the integral compressor.

Abstract: A power generation system may include: a first gas turbine system including a first turbine component, a first integral compressor and a first combustor to which air from the first integral compressor and fuel are supplied. The first integral compressor has a flow capacity greater than an intake capacity of the first combustor and/or the first turbine component, creating an excess air flow. A second gas turbine system may include similar components to the first except but without excess capacity in its compressor. A turbo-expander may be operatively coupled to the second gas turbine system. Control valves may control flow of the excess air flow from the first gas turbine system to at least one of the second gas turbine system and the turbo-expander, and flow of a discharge of the turbo-expander to an inlet of at least one of the first integral compressor and the second compressor.

Abstract: A power generation system may include a generator, and a gas turbine system for powering the generator, the gas turbine system including a turbine component, an integral compressor and a combustor to which air from the integral compressor and fuel are supplied, the combustor arranged to supply hot combustion gases to the turbine component, and the integral compressor having a flow capacity greater than an intake capacity of at least one of the combustor and the turbine component, creating an excess air flow. A turbo-expander may also power the generator. A first control valve control flow of the excess air flow along an excess air flow path to an inlet of the turbo-expander. An educator may be positioned in the excess air flow path for using the excess air flow as a motive force to augment the excess air flow with additional air. A discharge of the turbo-expander is supplied to an exhaust of the turbine component for an HRSG.

Abstract: A power generation system may include: a first gas turbine system including a first turbine component, a first integral compressor and a first combustor to which air from the first integral compressor and fuel are supplied. The first integral compressor has a flow capacity greater than an intake capacity of the first combustor and/or the first turbine component, creating an excess air flow. A second gas turbine system may include similar components to the first except but without excess capacity in its compressor. A turbo-expander may be operatively coupled to the second gas turbine system. Control valves may control flow of the excess air flow from the first gas turbine system to at least one of the second gas turbine system and the turbo-expander, and flow of a discharge of the turbo-expander to an exhaust of at least one of the first turbine component and the second turbine component.

Abstract: A method for adjusting startup floor pressure levels of HRSG steam circuits is implemented by a pressure controlling computing device including a processor and a memory. The method includes receiving a plurality of measured plant operating values associated with a HRSG steam circuit, identifying a plurality of candidate pressure levels for use in pressurizing the HRSG steam circuit, determining a calculated steam velocity level for each of the plurality of candidate pressure levels, identifying a steam velocity limit for a steam piping section of the HRSG steam circuit, selecting a lowest pressure level of the plurality of candidate pressure levels, wherein the lowest pressure level is associated with a determined calculated steam velocity level that does not exceed the identified velocity limit, and pressurizing the HRSG steam circuit to the selected lowest pressure level.

Abstract: A fuel delivery system is provided. The system includes a natural gas reformer configured to receive a flow of natural gas and a flow of air. The natural gas reformer combines the natural gas and the air in a reaction to produce a flow of reformate gas. The system also includes a mixing device coupled downstream from the natural gas reformer. The mixing device is configured to selectively mix amounts of the reformate gas, vaporized liquid fuel, and natural gas to produce a flow of mixed product fuel having predetermined operating parameters.

Abstract: A fuel heating system for use with a combined cycle gas turbine including a turbine outlet configured to channel a flow of exhaust gas towards a heat recovery steam generator is provided. The system includes a heat exchanger configured to channel a flow of fuel therethrough, and a plurality of heat transfer devices that each include an evaporator portion in thermal communication with the flow of exhaust gas and a condenser portion selectively thermally exposed to the flow of fuel. Each of the plurality of heat transfer devices are configured to conduct different grade heat from the exhaust gas to regulate a temperature of the fuel.

Abstract: A combined cycle power plant includes a gas turbomachine, a steam turbomachine operatively coupled to the gas turbomachine, and a heat recovery steam generator operatively coupled to the gas turbomachine and the steam turbomachine. The heat recovery steam generator includes a high pressure reheat section provided with at least one high pressure superheater and at least one reheater. The combined cycle power plant further includes a controller operatively connected to the gas turbomachine, the steam turbomachine and the heat recovery steam generator. The controller is selectively activated to initiate a flow of steam through the heat recovery steam generator following shutdown of the gas turbomachine to lower a temperature of at least one of the high pressure superheater and the at least one reheater and reduce development of condensate quench effects during HRSG purge of a combined cycle power plant shutdown.

Abstract: The present application describes a heat recovery steam generator. The heat recovery steam generator may include a superheater, a first turbine section, a first main steam line in communication with the superheater and the first turbine section, and a first prewarming line positioned downstream of the first main steam line such that a flow of steam from the superheater preheats the first main steam line without entry into the first turbine section.

Abstract: A system for heating fuel in a combined cycle gas turbine includes a fuel heat exchanger downstream from a turbine outlet, and the fuel heat exchanger has an exhaust gas inlet, an exhaust gas outlet, a fuel inlet, and a fuel outlet. A first exhaust gas plenum has a first exhaust gas inlet connection between the turbine outlet and a heat exchanger and a first exhaust gas outlet connection upstream from the exhaust gas inlet. A second exhaust gas plenum has a second exhaust gas inlet connection downstream from at least a portion of the heat exchanger and a second exhaust gas outlet connection upstream from the exhaust gas inlet.

Abstract: The present application and the resultant patent provide a combined cycle system with a flow of feed water therein. The combined cycle system may include a gas turbine, a steam turbine, a heat exchanger with the flow of feed water flowing therethrough, an expansion source for expanding the flow of feed water, and a supplemental power generation system positioned between the heat exchanger and the expansion source and driven by the flow of feed water.

Abstract: A combined cycle power plant startup system is provided. The system includes a steam turbine, a HRSG, a condenser, and a bypass system. The steam turbine may include a turbine section. The HRSG may be operably connected to the steam turbine for providing steam to the steam turbine. The HRSG may include a reheater. The bypass system may be configured to adjust the steam pressure downstream of the reheater by routing steam downstream of the reheater to the condenser. The bypass system may include at least one bypass line, at least one control valve operably connected to the at least one bypass line, a pressure gauge configured to monitor the steam pressure downstream of the reheater, and a controller configured to communicate with the pressure gauge and operate the at least one control valve.