Electronic Control of Marine Gas Turbine Engines

Abstract

The advantages of electronic controls in terms of accuracy and adaptability to differing requirements have been recognised for a long time. The application of these controls to gas turbine engines, has in the past been inhibited by their unreliability when compared with that of hydromechanical systems. Recent developments in constructional techniques of electronic controls however, have altered this situation, and control systems are now available which give reliabilities comparable with those available with the hydromechanical systems used hitherto.Electronic controls operate by modifying the fuel flow to the engine, and the interface equipment to perform this function must be chosen with care, taking account of the necessary speed of response and the requirements for modes of failure.The wide range of fuels which are burned in gas turbine engines and the possibility of salt-water and other forms of contamination pose peculiar problems in the design of the pumping element which have been successfully solved.In this paper a practical example is given of a control system for a gas turbine engine used for ship propulsion. The type of control, the control interface and the pump design are all discussed, and typical test results are published showing the control system performance during engine starting, steady running and transient operation. A brief description of the constructional techniques for the electronic control is also given.