Model-based design and fault-tolerant control of an actively redundant electromechanical flight control actuation system

As of today, the largest efforts to enable the introduction of EMAs in primary flight controls have focused on the reduction of the actuator components’ weight as well as on the improvement of their reliability at the required performance. These steps are certainly fundamental and have led to attaining a higher maturity level at which the deployment of EMAs in the front-line seems feasible. Still, very few has been done with regard to the fault management in electromechanical active-active actuation systems. A fault-tolerant control concept is thus herein developed with the objective of making such systems comparable to the state-of-the-art in terms of safety, reliability, and availability. An ample set of design recommendations and findings with respect to the application of electromechanical actuators in primary flight controls emerge from the design tasks carried out along this thesis. Furthermore, a number of model-based notions are established as design-support means; their aptness is demonstrated through experimental verification and validation. A special emphasis is made on the optimal design of the electromechanical actuators utilized throughout the development of the fault-tolerant control concept. The goal is to put forth a concept that is representative of real aerospace applications. Furthermore, all the adopted actuator control approaches attempt to observe the general goals of satisfactory performance and low complexity. Little regard is paid to the areas of power electronics design and thermal actuator sizing as these are not decisive aspects for the proof of concept—corresponding assumptions are given.