The development of medium-voltage direct current (MVDC) cable systems for wide-body all-electric aircraft (AEA) requires insulation technologies capable of operating reliably under reduced-pressure environments. Conventional underground cable insulation, designed for atmospheric conditions, exhibits degraded partial discharge (PD) and dielectric performance at low pressure, limiting its applicability to aerospace systems. This work presents a controlled experimental comparison between a conventional single-layer extruded insulation system and a micro-multilayer multifunctional electrical insulation (MMEI) architecture, in which all cable components are kept identical except for the insulation.
