Gas turbine control

摘要

A control system for a gas-coupled gas turbine engine particularly directed to control of the setting angle of the power turbine nozzle of the engine and to correlation of the power turbine nozzle setting with fuel supply and with operating parameters of the engine. The control provides for operation of the engine from closed to full open throttle, with closed throttle calling for idle speed of the engine. The initial stage of opening the throttle develops an increasing nozzle reference temperature signal which is matched with a turbine temperature signal to control a servo which varies the setting, and therefore area, of the turbine nozzle. After the initial stage of throttle opening, the reference temperature signal increases with engine speed, which increases in response to an increasing throttle signal. The actual level of the nozzle reference temperature is also a function of engine inlet temperature up to a given level of this temperature. Throttle position generates a speed reference signal which is matched with actual gas generator speed to control fuel supply to the engine. The speed reference signal is coordinated with the nozzle reference temperature signal so that there is a smooth transition from the increasing nozzle reference temperature over the initial range of throttle movement to the increasing engine speed reference signal over the remainder of the travel of the throttle up to or near 100% rated power output signal.