A control system for a gas turbine engine includes a processing system operable to control a speed of the gas turbine engine and a memory system. The memory system is operable to store instructions executable by the processing system to determine at least one performance parameter associated with a stall condition of the gas turbine engine and to incrementally adjust an acceleration rate of the gas turbine engine based on detecting a degraded stall line limit according to the at least one performance parameter.

A method of controlling an aircraft engine with an engine control system for limiting acceleration in response to reslam operation. The method includes triggering a reslam logic, detecting an acceleration that exceeds an acceleration threshold, and determining an elapsed time debit based on time elapsed from triggering of the reslam logic threshold. The elapsed time debit is inversely proportional to the elapsed time from triggering of the reslam logic and is utilized to set an engine acceleration reference value limit and maximum fuel rate limit.

A control system for a gas turbine engine includes a processing system operable to control a speed of the gas turbine engine and a memory system. The memory system is operable to store instructions executable by the processing system to determine at least one performance parameter associated with a stall condition of the gas turbine engine and to incrementally adjust an acceleration rate of the gas turbine engine based on detecting a degraded stall line limit according to the at least one performance parameter.

Systems and methods for controlling an gas turbine engine are provided. The method comprises receiving a requested engine speed and obtaining a shaft inertia of the engine, a steady state fuel flow for the requested engine speed, and a relationship between fuel flow and acceleration power generated by the fuel flow. A required fuel flow to obtain the requested engine speed is determined as a function of the requested engine speed, the shaft inertia of the engine, the steady state fuel flow for the requested engine speed, and the relationship between fuel flow and acceleration power generated by the fuel flow. A command to a fuel flow metering valve is output in accordance with the required fuel flow.

Systems and methods for controlling a gas turbine engine are provided. The system comprises an interface to a fuel flow metering valve for controlling a fuel flow to the engine in response to a fuel flow command and a controller connected to the interface and configured for outputting the fuel flow command to the fuel flow metering valve in accordance with a required fuel flow. The controller comprises a feedforward controller configured for receiving a requested engine speed, obtaining a steady-state fuel flow for the requested engine speed as a function of the requested engine speed, the steady-state fuel flow, and the relationship between fuel flow and gas generator speed, and determining the required fuel flow to obtain the requested engine speed and the relationship between fuel flow and gas generator speed.

The invention relates to a method for starting an aircraft turboshaft engine, said turboshaft engine comprising a combustion chamber, a compressor shaft on which a compressor wheel is mounted to feed compressed air to said combustion chamber, at least one starter connected to said shaft so as to provide it with a specified starting torque for driving it in rotation. The method comprises accelerating the compressor shaft during a first start-up phase, then stabilizing the rotational speed of the compressor shaft during a second start-up phase. During acceleration of the compressor shaft, the rotational speed of the shaft is regulated such that the acceleration of the shaft remains substantially constant.

The invention relates to a method and control system to control the speed of a centrifugal compressor operating within a vacuum pressure swing adsorption process to avoid an operation at which surge can occur and directly driven by an electric motor that is in turn controlled by a variable frequency drive. The claimed method determines the optimal speed for operation of the compressor along a peak efficiency operating line of a compressor map thereof. Speed of the compressor is adjusted by a feed back speed multiplier when the flow or other parameter referable to flow through the compressor is below a minimum and a feed forward multiplier during evacuation and evacuation with purge steps that multiplies the feed back multiplier to increase speed of the compressor and thereby avoid surge.

An assembly for an aircraft engine includes a rotational assembly, a starter, and a controller. The rotational assembly includes at least one rotor. The starter is coupled with the rotational assembly. The starter is configured to selectively drive rotation of the rotational assembly. The controller is configured to determine an acceleration threshold for a starter-assist only phase of an engine start sequence for the aircraft engine using a measured engine oil temperature for the aircraft engine, measure an acceleration of the rotational assembly during the starter-assist only phase, and identify a presence or an absence of insufficient starter acceleration for the starter-assist only phase by comparing the measured acceleration to the acceleration threshold. The presence of the insufficient starter acceleration is identified when the measured acceleration is less than the acceleration threshold. The absence of the insufficient starter acceleration is identified when the measured acceleration is greater than the acceleration threshold.

One aspect is an electrical augmentation system for a gas turbine engine. The electrical augmentation system includes an electric motor operably coupled to a shaft of the gas turbine engine, and an energy storage device operable to provide a temporary increased current source to the electric motor. The electrical augmentation system includes a control system having a torque demand anticipation circuit operable to determine an anticipated torque increase condition for the gas turbine engine. Based on the anticipated torque increase condition, the torque demand anticipation circuit commands a temporary torque increase by the electric motor using the energy storage device.

Certain embodiments of the disclosure may include systems and methods for boundary control during steam turbine acceleration. According to an example embodiment, the method can include receiving an indication the turbine is in an initial acceleration phase; receiving speed control parameter data from a plurality of sensors; receiving boundary control parameter data from a plurality of sensors; providing a control valve configured for controlling steam flow entering the turbine; determining the control valve position based on received speed control parameter data; determining the control valve position based on received boundary control parameter data; adjusting at least one boundary control parameter to the at least one boundary control parameter limit during turbine startup, wherein the value of a speed control parameter is simultaneously adjusted based on the adjusted at least one boundary control parameter; and adjusting the control valve position based at least on determined parameter data.