Abstract: The present disclosure provides pumped thermal energy storage systems that can be used to store and extract electrical energy. A pumped thermal energy storage system of the present disclosure can store energy by operating as a heat pump or refrigerator, whereby net work input can be used to transfer heat from the cold side to the hot side. A working fluid of the system is capable of efficient heat exchange with heat storage fluids on a hot side of the system and on a cold side of the system. The system can extract energy by operating as a heat engine transferring heat from the hot side to the cold side, which can result in net work output.

Abstract: The present disclosure provides pumped thermal energy storage systems that can be used to store and extract electrical energy. A pumped thermal energy storage system of the present disclosure can store energy by operating as a heat pump or refrigerator, whereby net work input can be used to transfer heat from the cold side to the hot side. A working fluid of the system is capable of efficient heat exchange with heat storage fluids on a hot side of the system and on a cold side of the system. The system can extract energy by operating as a heat engine transferring heat from the hot side to the cold side, which can result in net work output.

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 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 gas turbine system includes a compressor, a fuel source, a combustor, and a turbine. The compressor is configured to compress air. The fuel source is configured to supply fuel to a plurality of fuel manifolds. The combustor is configured to receive the air from the compressor, to receive the fuel from the plurality of fuel manifolds, and to combust the air and the fuel into combustion products. The turbine is configured to extract work from the combustion products. A fuel control valve is disposed within each of the plurality of fuel manifolds and is configured to throttle the fuel to the combustor when the gas turbine system is operating in an electrical island mode.

Abstract: Systems and methods for performing islanding operations are usable to monitor and collect plant loads and turbine loads of a power plant. Such monitoring and collecting can be used to preemptively determine islanding configurations. According to one embodiment of the invention, a system can be provided. The system can be operable to receive power generation unit information, receive power plant information of the power plant, determine an islanding configuration for the power plant, transmit the islanding configuration to the at least one power generation unit of the power plant, receive breaker status information of at least one breaker coupled to the at least one power generation unit of the power plant and for all breakers connecting power plant to an external grid, and control at least one power generation unit of the power plant.

Abstract: A level control system for controlling a liquid level in a vessel containing a two-phase fluid includes a plurality of sensors configured to measure parameters related to the vessel. The parameters include liquid level in the vessel, vapor flow rate leaving the vessel, pressure in the vessel, temperature of the vessel, and feed-liquid flow rate entering the vessel indicative of a state of the vessel. A predictive controller is configured to receive output signals from the plurality of sensors and predict a volume of liquid over a predetermined time period in the vessel based on output signals from the plurality of sensors and a variation in pressure, thermal load, or combinations thereof in the vessel. The controller is configured to generate a liquid level set point of the vessel based on the predicted volume of liquid in the vessel; and further control a liquid level in the vessel based on the generated liquid level set point by manipulating one or more control elements coupled to the vessel.

Abstract: A gas turbine system includes a compressor, a fuel source, a combustor, and a turbine. The compressor is configured to compress air. The fuel source is configured to supply fuel to a plurality of fuel manifolds. The combustor is configured to receive the air from the compressor, to receive the fuel from the plurality of fuel manifolds, and to combust the air and the fuel into combustion products. The turbine is configured to extract work from the combustion products. A fuel control valve is disposed within each of the plurality of fuel manifolds and is configured to throttle the fuel to the combustor when the gas turbine system is operating in an electrical island mode.

Abstract: A method for controlling a water level of a drum of a heat recovery steam generation system for a combined cycle power plant is provided. The method includes determining an optimum drum water level during start up operation of the heat recovery steam generation system based on a characteristic chart model. The characteristic chart model is generated based on a plurality of vapor pressures of the drum and a plurality of temperatures of drum metal at the time of the start up operation of the heat recovery steam generation system.

Abstract: A fuel system is provided and includes inert gas, fuel and air sources to provide a supply of inert gas, fuel and air, respectively, piping including valves delimiting cavities therein to which the inert gas, fuel and air are supplied such that the inert gas separates the respective cavities containing fuel and air, a pressure control valve disposed on the piping to modulate a pressure of the inert gas supplied to the piping and a controller coupled to the pressure control valve to control an operation thereof in accordance with at least variable pressures of the fuel and air in the respective cavities containing the fuel and the air.

Abstract: Systems and methods for performing islanding operations are usable to monitor and collect plant loads and turbine loads of a power plant. Such monitoring and collecting can be used to preemptively determine islanding configurations. According to one embodiment of the invention, a system can be provided. The system can be operable to receive power generation unit information, receive power plant information of the power plant, determine an islanding configuration for the power plant, transmit the islanding configuration to the at least one power generation unit of the power plant, receive breaker status information of at least one breaker coupled to the at least one power generation unit of the power plant and for all breakers connecting power plant to an external grid, and control at least one power generation unit of the power plant.

Abstract: Embodiments of the present invention incorporate a relatively slow acting valve to throttle the fuel flow through the compressor. Embodiments of the present invention seek to reduce the need for recirculating compressed fuel that is not needed by the turbomachine. This may increase the net power output and efficiency of a turbomachine-fuel gas compressor system.

Abstract: A method for controlling a water level of a drum of a heat recovery steam generation system for a combined cycle power plant is provided. The method includes determining an optimum drum water level during start up operation of the heat recovery steam generation system based on a characteristic chart model. The characteristic chart model is generated based on a plurality of vapor pressures of the drum and a plurality of temperatures of drum metal at the time of the start up operation of the heat recovery steam generation system.

Abstract: Embodiments of the invention can include methods and systems for controlling clearances in a turbine. In one embodiment, a method can include applying at least one operating parameter as an input to at least one neural network model, modeling via the neural network model a thermal expansion of at least one turbine component, and taking a control action based at least in part on the modeled thermal expansion of the one or more turbine components. An example system can include a controller operable to determine and apply the operating parameters as inputs to the neural network model, model thermal expansion via the neural network model, and generate a control action based at least in part on the modeled thermal expansion.

Abstract: A system includes sensors configured to measure vessel parameters. A signal processing unit receives sensor output signals and generates a first, second, third, fourth, and fifth filtered output signals representative of liquid level, gas flow rate, feed-liquid flow rate, vessel pressure, and vessel temperature, respectively. A flow demand control unit receives the first filtered output signal and generates an output signal representative of feed-liquid flow demand. A shaping unit receives the second, fourth, and fifth filtered output signals and generates an output signal representative of shaped gas flow rate. A liquid level control unit controls the liquid level within predetermined limits by controlling one or more components based on the output signals from the flow demand control unit, the shaping unit, and the third filtered output signal.

Abstract: A fuel system comprises a fuel nozzle having a first port and a second port, a first manifold connected to the first port, and a first inert gas buffer portion disposed between the first manifold and a source of compressed air.

Abstract: A level control system for controlling a liquid level in a vessel containing a two-phase fluid includes a plurality of sensors configured to measure parameters related to the vessel. The parameters include liquid level in the vessel, vapor flow rate leaving the vessel, pressure in the vessel, temperature of the vessel, and feed-liquid flow rate entering the vessel indicative of a state of the vessel. A predictive controller is configured to receive output signals from the plurality of sensors and predict a volume of liquid over a predetermined time period in the vessel based on output signals from the plurality of sensors and a variation in pressure, thermal load, or combinations thereof in the vessel. The controller is configured to generate a liquid level set point of the vessel based on the predicted volume of liquid in the vessel; and further control a liquid level in the vessel based on the generated liquid level set point by manipulating one or more control elements coupled to the vessel.

Abstract: Embodiments of the invention can include methods and systems for controlling clearances in a turbine. In one embodiment, a method can include applying at least one operating parameter as an input to at least one neural network model, modeling via the neural network model a thermal expansion of at least one turbine component, and taking a control action based at least in part on the modeled thermal expansion of the one or more turbine components. An example system can include a controller operable to determine and apply the operating parameters as inputs to the neural network model, model thermal expansion via the neural network model, and generate a control action based at least in part on the modeled thermal expansion.

Abstract: A system includes sensors configured to measure parameters related to a vessel including liquid level, gas flow rate, pressure in the vessel, temperature of the vessel, and feed-liquid flow rate. A signal processing unit receives sensor output signals and generates a first filtered output signal representative of liquid level, a second filtered output signal representative of gas flow rate, a third filtered output signal representative of feed-liquid flow rate, a fourth filtered output signal representative of vessel pressure, and a fifth filtered output signal representative of vessel temperature. A flow demand control unit receives the first filtered output signal and generates an output signal representative of feed-liquid flow demand. A shaping unit receives the second, fourth, and fifth filtered output signal and generates an output signal representative of shaped gas flow rate as a function of pressure, temperature, or combination thereof in the vessel.