Stability-Oriented Impedance Modeling, Analysis, and Shaping for Power Supply System in More-Electric Aircraft: A Review

More-electric aircraft (MEA) has evolved in the recent two decades due to their superiority in fuel efficiency, noise reduction, and reliability compared to conventional aircraft. The power supply systems, commonly regarded as distributed interactive systems, play a paramount role in MEA, yet are facing critical concerns in terms of their stability. Impedance is a key enabling tool to study the stability of such interactive systems and therefore contributes to better design optimization. Toward this end, this article presents a comprehensive review of the impedance modeling, stability analysis, and impedance shaping for power supply system in MEA. The three typical power supply system architectures of MEA are introduced and summarized in the first place. Then, existing studies on the impedance model are reviewed. Due to the nonlinear time-varying characteristics of the ac system, it needs to be linearized. This article discusses the characteristics and scope of applications of dq-axis linearization and harmonic linearization methods. In addition, this article highlights the aspects of the impedance stability analysis including dc and ac stability criterion. The strengths, limitations, and application scenarios of each criterion are summarized and discussed. Finally, impedance shaping methods, including structural reshaping, impedance parameter optimization, and system-level control, have also been surveyed and summarized.