Enhanced Fault Tolerance of Dual Three-Phase Permanent Magnet Motor With Three-Redundancy Control

Abstract

This article proposes a novel three-redundancy control for the dual three-phase permanent magnet (DTP-PM) motor to enhance the open-phase fault tolerance. Three redundancies can be operated individually or synergistically. Hence, the faulty redundancy can be disconnected from the system to address the open-phase fault. The fault tolerance can be significantly enhanced. Primarily, the structure of the DTP-PM motor is analyzed. Six phases of the DTP-PM motor are separated into three sets of orthogonal phases and considered three two-phase motors. Therefore, three redundancies can be established. Since orthogonal phases provide a balanced structure, the magnetomotive force of each redundancy can be well controlled. Then, a DTP-PM motor control system with three redundancies is established, and a potential topology for the proposed strategy is also illustrated. Furthermore, the basic voltage vectors for each redundancy are investigated. The reference voltage vectors can be modulated expediently. Finally, some simulations and experiments are carried out, validating the feasibility and effectiveness of the proposed strategy.