Rolls-royce Corporation

Cerith Davies

John Richard Webster

John James Anthony Cullen

Arthur Laurence Rowe

Marko Bacic

Marc Pons Perez

A method of controlling a gas turbine engine including receiving an instantaneous thrust demand for current operation of the engine, determining the inlet flow rate and/or the pressure ratio within the compressor of the engine and determining whether the inlet flow rate and/or the pressure ratio match the working line for the compressor. The angle of one or more vane of the compressor is adjusted according to a closed control loop if the inlet flow rate and/or pressure ratio lie outside said desired range in order to adjust the inlet inflow rate and/or pressure ratio to meet the working line. The fuel flow to the engine combustor is adjusted concurrently in order to meet the thrust demand.

Gas turbine engine flow control

A compressor variable stator vane arrangement comprises at least one stage of variable stator vanes. A speed sensor measures the rotational speed of the compressor rotor. A pressure sensor measures the outlet pressure of the compressor. A second pressure sensor, a temperature sensor and a third pressure sensor measure the total inlet pressure, the temperature and the ambient pressure at the inlet of the gas turbine engine. A processor determines a target operating line as a function of ambient pressure and total inlet pressure. The target operating line is defined to ensure the gas turbine engine operates simultaneously at both the minimum required compressor speed and the minimum required compressor outlet pressure when commanded to idle to minimize idle thrust and fuel burn. The processor determines if the operating point of the compressor, defined in terms of corrected outlet pressure and corrected rotational speed of the compressor rotor is above or below the target operating line of the compressor. The processor adjusts the angle of the variable stator vanes to make the operating point operate on the target operating line.

Gas turbine engine compressor variable stator vane arrangement

With an active magnetic bearingthere is a limit to the available rapidity of response to transient loadings upon a target or rotor. Thus, in accordance with the present invention, storage deviceshold an electrical voltage VS significantly greater than the normal supply voltage V provided by a normal electrical source. In such circumstances when a very large transient loading is detected on the bearinga switchdischarges the supply voltage VS across the coilin order that a more rapid increase and higher value inductance current IT is presented to the coilin response to that variable loading upon the target/rotor. The electrical discharge from the storage devicecan be adjusted using the switchor mixing the storage devicesas required for an appropriate discharge signal shape. Generally, the active magnetic bearingis controlled by a controller device which monitors target/rotorposition in order to determine transient loading and therefore switching of the storage device

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Uttoxeter, United Kingdom

Cerith Davies