Optimal design and analysis of a dual-3phase permanent magnet motor with fault tolerant capability

Compared with other multiphase machines, dual three-phase machines are able to take advantage of off-the-shelf three-phase inverters. Though the output torque decreases under post-fault conditions, the post-fault control strategies of them are simple, and their post-fault performance is steady. Therefore, the market of dual three-phase machines is promising in the future. In this paper, the design principle, operating characteristics behavior of the dual three-phase machine are investigated. Firstly, the winding arrangement and slot-pole combination of the dual three-phase machine is analyzed. The performance of different schemes iscompared, and the optimal scheme of winding arrangement and slot-pole combination for the dual three-phase machine is proposed. Moreover, the machine adopting the proposed scheme is designed. Secondly, operating characteristics of the dual three-phase machine under healthy conditions is analyzed. The possible fault terms of the machine is summarized. Comparing with conventional constant magnetomotive force, the advantage of the dual three-phase machine is significant. The effectiveness of the theoretical analysis and simulations is validated by the comparison.