Digital start-up control of the small turbojet engine MPM-20

The main thesis of this paper considers the possibilities and difficulties of switching from hydromechanical engine control to FADEC (digital) engine control. Regarding different specifications and elements in system, possible errors, advantages and disadvantages, each method has its specific properties of behavior in specific environments and applications. When considering our controlled system, the MPM-20 small turbojet engine, it is a challenge to propose functional control system with backups and with slight possibility of errors during or before operation. In this paper we propose methods of backups for specific elements, prestart diagnostics and on-line diagnostics.