Design of a 600kW ring-type direct-drive flux-switching permanent magnet machine for aerospace main propulsion

Abstract

More-Electric flight is one of the main objectives of the aerospace industry for the future. Foraerospace applications, electrical machines providing high torque density are paramount for theviability of direct-drive electrical propulsion of aircraft. Besides low-weight and high torquecapability, a candidate solution should also be inherently fault tolerant for it to be used in aerospace.For these reasons a first solution based on Flux-Switching Permanent Magnet (FSPM) machines for anexemplary application of a helicopter main rotor drive was investigated, since these machines haveshown high torque-to-weight ratios and high efficiency during research in the last decade. Despite this,the task of designing a machine appropriate for this application goes beyond the electromagneticdesign and into the area of mechanical design much deeper than for traditional designs: Thelightweight nature of such an iron-based machine makes the design of support structures and airgapcontrol challenging and requires unconventional approaches. This paper presents the main design stepsand first experimental results for such a machine.