Motor Design Considerations for Supersonic Electric Aircraft

This paper presents the design and analysis of a high-speed, high voltage, high-power dual-rotor motor (DRM) for supersonic electric turbofan propulsion. In the proposed electric turbofan, the combustion chamber and turbine are eliminated, and a high-speed electric motor directly powers a multistage fan and compressor. The DRM features a dual-rotor topology, consisting of a permanent magnet (PM) rotor and a wound field (WF) rotor mounted on the same shaft and sharing a common stator with the supersonic electric turbofan. A 9-phase architecture is adopted to enhance power density, efficiency, and fault tolerance compared to conventional 3-phase systems. A finite element analysis (FEA) is conducted to evaluate flux densities, insulation feasibility, and electromagnetic performance. A 36-slot, 8-pole configuration is selected for optimal flux distribution and mechanical constraints. Experimental validation using a scaled-down prototype confirms the analytical and simulation results, demonstrating the feasibility of the proposed DRM for next-generation supersonic electric propulsion.