Fault-tolerant stator flux oriented decoupling control for dual three-phase permanent magnet motor without diagnosis and reconfiguration

In this paper, the fault-tolerant capability of the existing stator-flux-oriented decoupling control (SFOC) for the DTP-PM motor is investigated, and a simple fault-tolerant SFOC is further designed to enhance fault tolerance. Firstly, the mathematical model of the DTP-PM motor in the stator-flux-oriented rotating coordinate system is analyzed. An SFOC is proposed to guarantee healthy operation performance, considering torque, flux linkage, and harmonic currents. Secondly, the coupling relationship under open-phase conditions is assessed. The assessed result shows that the coupling relationship between the harmonic and fundamental components results in conflicts and poor post-fault operation. Thirdly, the proposed SFOC includes an automatic deactivation module to detect conflicts with a variable threshold. The conflicted harmonic current controllers can be excluded automatically. Hence, fault-tolerant control can be remedied without diagnosing the specific fault scenario, and excellent fault-tolerant capability can be achieved. Finally, experiments on a DTP-PM motor are carried out to verify the feasibility and effectiveness of the proposed strategy.