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Comparison of Three-Phase and Six-Phase High-Power Ultra-High-Speed Machine for Portable Mechanical Antenna

One of the emerging applications of the ultra-high-speed machine (UHSM) is a mechanical-based antenna (AMEBA) for portable wireless communication in the RF-denied environment. With higher power density, efficiency, and lower torque pulsation, the multi-phase UHSM can be a better substitute compared to the conventional three-phase UHSM in the AMEBA application, where portability and efficiency are the top priority. This paper presents the comparison of the three-phase and six-phase UHSM in terms of the design and performance characteristics, considering their use in a safety-critical AMEBA application. For a fair comparison, both models are designed using the same multi-physics design process. The models are optimized to maximize the efficiency, power-density, and design-safety-margin with multi-disciplinary constraints of the AMEBA system. Both models' key performances, such as the torque profile, efficiency map, back-electromotive force (EMF), temperature distribution, and developed stress, are compared by intensive simulation using finite element analysis (FEA). Finally, the optimized three-phase and six-phase UHSM prototypes (2 kW rated shaft power at 500 000 r/min) are fabricated with the same volume and same rotor geometry to validate the simulation results.