Electric Actuation For Flight & Engine Control System: Evolution, Current Trends & Future Challenges

The development of reliable electrical actuation systems for aircraft flight & engine control application has been evolving recently to eliminate hydraulic systems from engine and thus improve safety, efficiency, reliability, and maintainability and the common objective to conserve energy, reduce environmental pollution. This paper will review the architecture in electric actuators technology including electro-hydrostatic actuators (EHA) and electro-mechanical actuators (EMA) focusing on electric motor drives-including electronic power converter and electric motors technology. The aim of this work is to analyze and evaluate the possibility of introducing electro-mechanical actuators (EMAs) in more electric aircraft (MEA) and more electric engine (MEE) applications. The overall requirements for performance, availability including fault and jam tolerance, interfaces and physical attributes will be discussed to optimize the weight of such actuator systems with minimum added redundancy in the electrical machine including direct drive and gear mechanism, power converter architecture. The design of the power converter including centralized and distributed design for control and power drive electronics will be described. The EMA design for MEE has to consider the severe environmental constraints regarding to the wide operational temperatures. This constraint concerns the electric motor, the power electronics including possible use of wide band gap electronics such as SiC, the position sensors and the mechanical parts. It will also review electrical power interface issues including electric power and flight control computer electronics interface and the design considerations to minimize weight cost and improve reliability as well as civil certification objectives.