Optimal sizing and design of electric drive systems for aerospace actuation applications considering centralised and distributed topologies

The aviation industry is moving towards more electric aircraft. This involves the replacement of conventional mechanical, pneumatic, and hydraulic systems with electrical solutions. The motivation for this is to reduce system mass and operating costs, increase efficiency and availability while maintaining reliability and performance. This thesis presents a multifaceted design toolbox for optimal sizing of aerospace electric drive systems with long feeder cables. The design tool is applied to a flap actuation sizing case study. The drive components considered are the power electronics, EMI input filter, LC output filter, cable, machine, and gearbox. The toolbox’s inputs are design requirements defined by the system’s power, lifetime profile, failure rate, operating environment, and power quality. Models and procedures for each component within the toolbox determine their respective mass, volume, efficiency, thermals, failure rate, dynamics, power quality, and component parameters. The models are coupled with one another such that variation of one parameter lead to a change in another. The system is sized with the main objective of minimising its overall mass while ensuring design requirements are met. Analytical sizing and parameter determination procedures have been developed for all considered components. The capabilities of the proposed toolbox are demonstrated by using it to optimally size and design the electrical flap actuation drive system of an Airbus A320-200. Two different topologies are compared, centralised and distributed. Through the analysis and results, it was concluded that distributed is superior to the centralised topology, offering less mass and reduced complexity. The novelties of this research include: • A new sizing algorithm for surface mounted permanent magnet synchronous machines suitable. • Development of design toolbox for optimal aerospace electric drive system design consisting of high fidelity inter-domain dependent models that explicitly considers the relationship between mass, volume, electrical, electromechanical, thermal, mechanical, failure rate, and lifetime profile. The considered components are the machine, cable, LC output filter, inverter, parallel plate finned heat sink, EMI input filter, inductors, and capacitors. • Utilisation of aforementioned toolbox to assess the merits and drawbacks of optimised aerospace electric drive designs for both centralised and distributed topologies