Postfault Strategy of Universal Control for Dual Three-Phase PMSM Under Single Open-Phase Fault Considering Current Amplitude

Dual three-phase permanent-magnet synchronous motors (PMSMs) are becoming more popular in safety-critical applications such as aircraft system and electric vehicles, primarily due to their robust fault-tolerant capabilities. Recently, natural fault-tolerant control methods have drawn attentions for their abilities to avoid the complexities of control structure reconfiguration, fault diagnosis, and current reference adjustments. However, the post-fault performances, particularly regarding the stator copper loss and the current amplitude, have remained uncertain or uncontrolled in most of reconfigurationless control methods. Aiming to fill this gap, the post-fault strategy has been investigated for dual three-phase PMSM with single open-phase fault with universal control structure. It is revealed that the post-fault performance under open-phase fault can be determined by the positive-sequence current in harmonic subspace. The amplitude model of each phase current has been established as a function of the current amplitude ratio and the phase shift between dual three-phase windings. On this basis, the maximum torque (MT) can be achieved by the universal control method under post-fault condition. The experimental results are presented to illustrate the effectiveness of the proposed method.