Dynamic System Modeling and Stability Assessment of an Aircraft Distribution Power System using Modelica and FMI

Abstract

In this work, the electrical distribution system of a Boeing 747 aircraft is implemented in Modelica. The electrical system is modeled in detail as far as generation and loads are concerned, aiming to capture any relevant dynamics and instabilities that can ensue during the aircraft’s operation; while the power electronic interfaces of the loads are represented using averaged models. Small signal analysis is conducted at different operating points, aiming to capture relevant dynamics. Additionally, small signal analysis and time domain simulations are carried out to identify operational regions where low damping of unstable oscillations can occur, in order to characterize control loops interactions and system states. Finally, this paper proposes countermeasures for load startup and required controls that can alleviate any potential instabilities.