The design of more-electric engine power systems

Rights statement
Awarding institution
  • University of Strathclyde
Date of award
  • 2024
Thesis identifier
  • T16865
Person Identifier (Local)
  • 201786897
Qualification Level
Qualification Name
Department, School or Faculty
  • The More-Electric Aircraft (MEA) concept is now a well-established concept, following its introduction and development over the previous couple of decades. MEA systems are underpinned by state-of-the-art technologies to realise the reduction of CO2 emissions and increased the effectiveness of on-board power transmission. The More-Electric Engine (MEE) concept is increasingly being seen as a complementary solution for MEA applications. Within this concept, the engine auxiliary systems such as fuel pumps, oil pumps and actuation systems will be replaced by electrically driven equivalents and power will be extracted from multiple different engine shafts for electrical generation, with the potential to achieve significant fuel savings. However, with these changes, a dedicated high-integrity and flexibly reconfigurable MEE multiple-channel power architecture is required. When designing a multiple-channel power architecture for MEE´╝îit should comply with relevant power system design certification standards, requiring the application of a multi-disciplinary design methodology. In this thesis, key design certification and airworthiness standards are reviewed in order to identify those applicable to MEE design. Combining these with traceable qualitative and quantitative design logic, the first power system design rule set for MEE power system architecture baselining is established. Building on this foundational knowledge base, candidate novel multiple-channel power architectures are proposed and evaluated. These studies determine that a high degree of controllability and redundancy is key to achieving high system reliability and resilience in MEE power system architectures. In addition, a review of the research literature in this thesis is shown to reveal a shortage of proposed design and optimisation processes for flexible and redundant MEE-type power systems, making it difficult to maximise the design value of a feasible solution. As interdisciplinary and multi-system design processes can be time-consuming and laborious, this thesis instead presents a concurrent design (Co-design) methodology, addressing both MEE power architecture concepts and power management functions. This novel design process includes an initial coarse optimisation to determine the design space boundaries and exclude unsuitable and over-designed solutions for further detailed design, reducing design iterations. A subsequent collaborative synthesis stage for the concurrent design process is then proposed, in which fault scenario case studies and load shedding factor are used to verify the robustness of the combined MEE architecture and power management solutions to off-nominal operating conditions. This enables the refinement of the solution-space by using the simulated results to highlight the areas of the MEE power architecture that can be further optimised, demonstrating the benefits of knowledge-based collaborative design as a process for multi-criteria design. The contributions to the design of MEE power systems architectures presented in this thesis hence provide end-to-end value to the academic and industrial research community in the formation and design of new MEE concepts, with wider application to technologically-adjacent applications (such as hybrid electric aircraft, or high-integrity dc microgrids) also possible.
Advisor / supervisor
  • Norman, Patrick
  • Burt, Graeme
Resource Type