According to an aspect, a correction factor for a fuel flow of a fuel system of an engine is determined. A nominal fuel flow is determined based on a metering valve stroke. The correction factor is applied to the nominal fuel flow to produce an estimated fuel flow to control combustion in the engine.

Systems and methods for adjusting airflow distortion in a gas turbine engine using a secondary airflow passage assembly are disclosed. A gas turbine engine can include a compressor section, a combustion section, and a turbine section in series flow and defining at least in part an engine airflow path. A casing can enclose the gas turbine engine and be at least partially exposed to a bypass airflow. The gas turbine engine can further include a secondary airflow passage assembly comprising a door and a duct, the duct defining an inlet located on the casing, the duct defining an outlet in airflow communication with the engine airflow path, the duct comprising an airflow passage extending between the inlet and outlet. The door can be moveable between an open and closed position to allow a portion of the bypass airflow to flow through the airflow passage to adjust airflow distortion.

A system for a machine component includes at least one local transmitter/receiver. At least one device is associated with a component and configured to communicate with the at least one local transmitter/receiver through wireless signals. Shielding surrounds both the local transmitter and the device for containing the wireless signals proximate to the component. A remote processing unit is disposed outside of the shielding in communication with the local transmitter/receiver. A control system and method are also disclosed.

A bowed rotor prevention system for a gas turbine engine of an aircraft is provided. The bowed rotor prevention system includes a bowed rotor prevention motor operable to drive rotation of a starting spool of the gas turbine engine through an engine accessory gearbox. The bowed rotor prevention system also includes a controller operable to engage the bowed rotor prevention motor and drive rotation of the starting spool until a bowed rotor prevention threshold condition is met or a bowed rotor prevention shutdown request to halt rotation of the starting spool is received.

A bowed rotor prevention system for a gas turbine engine of an aircraft is provided. The bowed rotor prevention system includes a gear train and a bowed rotor prevention motor operable to drive rotation of a starting spool of the gas turbine engine through the gear train at a substantially constant speed upon engine shutdown until an energy storage source is depleted.

A bowed rotor start mitigation system for a gas turbine engine is provided. The bow rotor start mitigation system includes a controller operable to receive a speed input indicative of a rotor speed of the gas turbine engine and a measured temperature of the gas turbine engine. The controller is further operable to drive motoring of the gas turbine engine by oscillating the rotor speed within a motoring band for a motoring time based on the measured temperature when a start sequence of the gas turbine engine is initiated.

A communication adapter of a gas turbine engine of an aircraft includes a communication interface configured to wirelessly communicate with an offboard system and to communicate with an engine control of the gas turbine engine. The communication adapter also includes a memory system and processing circuitry configured to check for a change of an identifier associated with the engine control, check for a loss of a plurality of remote dynamic data recording parameters from the engine control, and pass a request to update the remote dynamic data recording parameters from the offboard system through the communication adapter to the engine control based on detecting the change of the identifier. The processing circuitry is further configured to reload an existing configuration of the remote dynamic data recording parameters at the engine control based on determining that the loss of the remote dynamic data recording parameters has occurred.

The present disclosure relates to a hydraulic control system for a thrust reverser of an aircraft turbofan nacelle. The hydraulic control system includes devices for actuating and controlling the reverser having hydraulic locks and cylinders, the corresponding hydraulic solenoid valves, and sensors. The turbofan includes a full-authority electronic computer or aircraft having an avionics computer that gives reverse thrust commands. The system further includes an electronic concentration module, different from the computer, which concentrates the data relating to the operation of the reverser actuation and control devices. The module includes internal contact switches for controlling the solenoid valves, a device for monitoring the sensors, a device for analog or digital processing of the data, and a bus for communication with the computer.

An emissions control system for a gas turbine system includes a reducing agent supply, at least one sensor, at least one valve, and a controller. The reducing agent supply has one or more conduits configured to couple to one or more fluid pathways of the gas turbine system, which are fluidly coupled to a flow path of an exhaust gas from a combustor through a turbine of the gas turbine system. The at least one sensor is configured to obtain a feedback of one or more parameters of the gas turbine system, which are indicative of a visibility of emissions of the exhaust gas. The at least one valve is coupled to the reducing agent supply. The controller is communicatively coupled to the at least one sensor and the at least one valve, such that, in response to the feedback, the controller adjusts the at least one valve to adjust a flow of the reducing agent to reduce the visibility of the emissions of the exhaust gas.

Provided is a method and system of positive and negative sequence rotor currents control for DFIGs under a single dq-PI control structure, comprising: adjusting the negative sequence rotor current reference

[00001]$\stackrel{.fwdarw.}{I}{\overline{{}_r}}_{\_ref-\ast }$

according to the negative sequence stator terminal voltage to obtain a reference adjustment value

[00002]$\stackrel{.fwdarw.}{I}{\overline{{}_r}}_{\_com-\ast }$

; converting the reference adjustment value to the forward-rotating dq coordinate system and superimposing it with the positive sequence rotor current reference as the input of a PI-regulator-based current feedback controller to uniformly control the positive and negative sequence rotor current; determining the output voltage reference of the rotor-side converter by the PI-regulator-based current feedback controller, according to which, the switching signal of the rotor-side converter can be determined through the SPWM function, controlling the turn-on and turn-off of the bridge arms of the rotor-side converter to form the output voltage. It realizes the control of the positive and negative rotor currents under the single dq-PI control structure, retaining the good control performance of the control structure for the positive sequence rotor current, and enabling the control of the negative sequence rotor current under unbalancing conditions, with a control structure with lower order and lower complexity compared to the existing control structures for realizing the DFIG positive and negative sequence current control.