Abstract: A control system for a gas turbine engine, a method for controlling a gas turbine engine, and a gas turbine engine are disclosed. The control system may include a hybrid model predictive control (HMPC) module, the HMPC module receiving power goals and operability limits and determining a multi-variable control command for the gas turbine engine, the multi-variable control command determined using the power goals, the operability limits, actuator goals, sensor signals, and synthesis signals. The control system may further include system sensors for determining the sensor signals and a non-linear engine model for estimating corrected speed signals and synthesis signals using the sensor signals, the synthesis signals including an estimated stall margin remaining. The control system may further include a goal generation module for determining actuator goals for the HMPC module using the corrected speed signals and an actuator for controlling the gas turbine engine based on the multivariable control command.

Abstract: A control system for a gas turbine engine including a power turbine is disclosed. The control system may also include an outer loop control module to determine a torque request. The outer loop control module may include a feedback control component operative to provide regulation of the power turbine, a feed-forward component operative to anticipate a load on the power turbine, and a hybrid control component operative to prevent output of a torque request that cannot currently be delivered by the power turbine. The control system may also include an inner loop control module to receive the torque request from the outer loop control module, to determine fuel flow and inlet guide vane schedules based at least in part on the received torque request, and to send signals to control a gas generator of the gas turbine engine according to the determined fuel flow and inlet guide vane schedules.

Abstract: A control system for a gas turbine engine including a power turbine is disclosed. The control system may include a control module to receive engine operating goals and an estimated current engine state, wherein the estimated current engine state is produced by a model-based estimation module using a bandwidth signal produced by an adaptation logic module. The control module is operative to determine fuel flow, inlet guide vane schedules and stability bleed schedules based at least in part on the received engine operating goals and the estimated current engine state, and to send signals to a gas generator of the gas turbine engine in order to control the gas generator according to the determined fuel flow, inlet guide vane schedules and stability bleed schedules.

Abstract: A control system for a gas turbine engine, a method for controlling a gas turbine engine, and a gas turbine engine are disclosed. The control system may include a nozzle scheduler for determining an exhaust nozzle position goal based on a nozzle schedule of exhaust nozzle positions related to flight conditions. The control system may further include a control module for determining a control command for the gas turbine engine. The control command may include, at least, a fuel flow command and an exhaust nozzle position command and the control command may be based on, at least, the exhaust nozzle position goal and an estimated thrust value. The control system may further include an actuator for controlling the gas turbine engine based on the control command.

Abstract: A system and methods are provided for controlling turboshaft engines. In one embodiment, a method includes receiving input signals for a collective lever angle (CLA) command and real-time power turbine speed (NP) of an engine, determining system data for engine effectors by the control unit based on the input signals for the collective lever angle (CLA) command and the real-time power turbine speed (NP) based on an integrated model for the turboshaft engine including a model of a gas generator section of the turboshaft engine and a model of a power turbine and rotor load section of the turboshaft engine. The method may also include determining control output based on model-based multi-variable control including optimization formulation and a constrained optimization solver. The method may also include outputting one or more control signals for control of the turboshaft engine.

Abstract: A system for controlling an absorption chiller includes feedback control loops determining adjustments to system cooling and heating capacities and a controller for simultaneously adjusting positions of an energy input valve, a hot water valve, and a chilled water valve. The controller adjusts valves based on desired adjustments to system cooling and heating capacities and performance maps characterizing relationships between cooling capacity and heating capacities and valve positions. A method for controlling an absorption chiller includes the step of obtaining a performance map characterizing heat energy input to cooling and heating loops as functions of valve positions. To obtain the map, the hot water valve is held in a substantially constant position while the chilled water valve is modulated. Similarly, the hot water valve is modulated while the chilled water valve is held in a substantially constant position.

Abstract: A control system for a gas turbine engine, a method for controlling a gas turbine engine, and a gas turbine engine are disclosed. The control system may include a hybrid model predictive control (HMPC) module, the HMPC module receiving power goals and operability limits and determining a multi-variable control command for the gas turbine engine, the multi-variable control command determined using the power goals, the operability limits, actuator goals, sensor signals, and synthesis signals. The control system may further include system sensors for determining the sensor signals and a non-linear engine model for estimating corrected speed signals and synthesis signals using the sensor signals, the synthesis signals including an estimated stall margin remaining. The control system may further include a goal generation module for determining actuator goals for the HMPC module using the corrected speed signals and an actuator for controlling the gas turbine engine based on the multivariable control command.

Abstract: A control system for a gas turbine engine, a method for controlling a gas turbine engine, and a gas turbine engine are disclosed. The control system may include a hybrid model predictive control (HMPC) module, the HMPC module receiving power goals and operability limits and determining a multi-variable control command for the gas turbine engine, the multi-variable control command determined using the power goals, the operability limits, actuator goals, sensor signals, and synthesis signals. The control system may further include system sensors for determining the sensor signals and a non-linear engine model for estimating corrected speed signals and synthesis signals using the sensor signals, the synthesis signals including an estimated stall margin remaining. The control system may further include a goal generation module for determining actuator goals for the HMPC module using the corrected speed signals and an actuator for controlling the gas turbine engine based on the multivariable control command.

Abstract: A control system for a gas turbine engine is disclosed. The control system may include a computer processor. The control system may also include an outer loop control module programmed into the computer processor to determine a torque request based at least in part on a real-time collective lever angle command. The control system may also include an inner loop control module programmed into the computer processor to receive the torque request from the outer loop control module, to determine fuel flow and inlet guide vane schedules based at least in part on the received torque request, and to send signals to a gas generator of the gas turbine engine in order to control the gas generator according to the determined fuel flow and inlet guide vane schedules.

Abstract: A system for controlling an absorption chiller includes feedback control loops determining adjustments to system cooling and heating capacities and a controller for simultaneously adjusting positions of an energy input valve, a hot water valve, and a chilled water valve. The controller adjusts valves based on desired adjustments to system cooling and heating capacities and performance maps characterizing relationships between cooling capacity and heating capacities and valve positions. A method for controlling an absorption chiller includes the step of obtaining a performance map characterizing heat energy input to cooling and heating loops as functions of valve positions. To obtain the map, the hot water valve is held in a substantially constant position while the chilled water valve is modulated. Similarly, the hot water valve is modulated while the chilled water valve is held in a substantially constant position.