Abstract: A system includes the HRSG having an economizer disposed along a fluid flow path, and a drum disposed along the fluid flow path downstream of the economizer. The HRSG also includes a drum level control module configured to modulate an amount of the fluid provided to the drum along the fluid flow path and a supplemental control module configured to control an amount of the fluid in a different manner than the drum level control module. The heat recovery steam generator also includes a drum level event controller configured to monitor a rate of change of a level of the fluid in the drum. If the rate of change is over a threshold value, a signal goes to the supplemental control. If the rate of change is less than or equal to the threshold value, the signal goes to the drum level control module.

Abstract: A method of controlling a heat recovery steam generator (HRSG) includes measuring a first regulated output of the HRSG and a second regulated output of the HRSG. The method includes comparing the first regulated output to a first setpoint defining a first target output to generate a first error signal and comparing the second regulated output to a second setpoint defining a second target output to generate a second error signal. The method also includes generating, by a controller implementing a multivariable control algorithm having as inputs the first error signal and the second error signal, control signals to control the HRSG to adjust values of the first regulated output and the second regulated output.

Abstract: A system includes the HRSG having an economizer disposed along a fluid flow path, and a drum disposed along the fluid flow path downstream of the economizer. The HRSG also includes a drum level control module configured to modulate an amount of the fluid provided to the drum along the fluid flow path and a supplemental control module configured to control an amount of the fluid in a different manner than the drum level control module. The heat recovery steam generator also includes a drum level event controller configured to monitor a rate of change of a level of the fluid in the drum. If the rate of change is over a threshold value, a signal goes to the supplemental control. If the rate of change is less than or equal to the threshold value, the signal goes to the drum level control module.

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: A method of controlling a heat recovery steam generator (HRSG) includes measuring a first regulated output of the HRSG and a second regulated output of the HRSG. The method includes comparing the first regulated output to a first setpoint defining a first target output to generate a first error signal and comparing the second regulated output to a second setpoint defining a second target output to generate a second error signal. The method also includes generating, by a controller implementing a multivariable control algorithm having as inputs the first error signal and the second error signal, control signals to control the HRSG to adjust values of the first regulated output and the second regulated output.

Abstract: A system and method control condensate formation within headers of a heat recovery steam generator (HRSG) in a power generation facility. The system includes measurement devices to measure first parameters including pressure at respective first locations within the power generation facility. A model estimates second parameters at second locations within the power generation facility. A prediction model outputs a prediction of time of condensate formation on each of the headers based on the first parameters and the second parameters, and a controller controls the condensate formation based on the prediction.

Abstract: A system configured to decrease the emissions of a power plant system during transient state operation is disclosed. In one embodiment, a system includes: at least one computing device adapted to adjust a temperature of an operational steam in a power generation system by performing actions comprising: obtaining operational data about components of a steam turbine in the power generation system, the operational data including at least one of: a temperature of the components and a set of current ambient conditions at the power generation system; determining an allowable operational steam temperature range for the steam turbine based upon the operational data; generating emissions predictions for a set of temperatures within the allowable steam temperature range; and adjusting the temperature of the operational steam based upon the emissions predictions.

Abstract: A system configured to decrease the emissions of a power plant system during transient state operation is disclosed. In one embodiment, a system includes: at least one computing device adapted to adjust a temperature of an operational steam in a power generation system by performing actions comprising: obtaining operational data about components of a steam turbine in the power generation system, the operational data including at least one of: a temperature of the components and a set of current ambient conditions at the power generation system; determining an allowable operational steam temperature range for the steam turbine based upon the operational data; generating emissions predictions for a set of temperatures within the allowable steam temperature range; and adjusting the temperature of the operational steam based upon the emissions predictions.

Abstract: A method includes blending a first fuel with a second fuel in a ratio to produce a third mixed fuel. The first fuel has a first heating value, the second fuel has a second heating value, and the third mixed fuel has a third heating value. In addition, the first heating value is different than the second heating value. The method also includes feedforward controlling the third heating value of the third mixed fuel via prediction and correction of a fuel flow rate of the first and/or second fuels to adjust the ratio of the first and second fuels based at least in part on a comparison between a measurement and a target for the third heating value.

Abstract: Systems and methods for analyzing power plant data include accessing data for one or more monitored parameters, generating a continuous time-series profile model (e.g., by generalized additive model and/or principal curves techniques) of selected parameters during instances of at least one given type of power plant operation, and conducting shape analysis by comparing the continuous time-series profile model of selected monitored parameters to an entitlement curve representing ideal performance for the at least one given type of power plant operation. Data associated with the profile modeling and shape analysis techniques may be provided as electronic output to a user. Additional steps or features may involve determining a capability index for selected monitored parameters, clustering together identified groups of profile models having similar profiles, monitoring and/or optimizing parameters to identify and improve power plant performance.

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: 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: A method includes blending a first fuel with a second fuel in a ratio to produce a third mixed fuel. The first fuel has a first heating value, the second fuel has a second heating value, and the third mixed fuel has a third heating value. In addition, the first heating value is different than the second heating value. The method also includes feedforward controlling the third heating value of the third mixed fuel via prediction and correction of a fuel flow rate of the first and/or second fuels to adjust the ratio of the first and second fuels based at least in part on a comparison between a measurement and a target for the third heating value.

Abstract: Methods and apparatus for fast starting and loading a combined cycle power system are described. In one example embodiment, a method for starting a combined cycle power generation system is provided. The system includes a gas turbine and a steam turbine. The method includes loading the gas turbine at a loading rate that is facilitated to be at an increased loading rate, setting a first predetermined value for a bypass pressure set point for high-pressure steam, and increasing the first predetermined value to a second predetermined value at a predetermined rate.