volume | PIER Journals

Abstract

High reliability and stability are essential for drive systems in intelligent inspection robots used in the power industry. To meet this requirement, this study investigates dual three-phase synchronous reluctance motors and proposes a five-leg fault-tolerant drive strategy based on direct-torque control (DTC). Unlike conventional dimension-reduction coordinate transformation methods that require isolating the faulty phase, which often leads to degraded system performance, the proposed approach introduces a bridge-arm sharing technique. By electrically coupling the faulty phase with a healthy phase, the spatial voltage vector distribution was reconstructed, enabling the reutilization of the faulty phase windings. Under single-phase fault conditions, the method effectively synthesizes the missing voltage vectors, preserves a circular flux linkage trajectory in the α-β subspace, suppresses 5th and 7th harmonics, and improves the current waveform quality. Simulation results verify that the strategy delivers superior harmonic suppression, reduced torque ripple, and enhanced system reliability, offering a novel technical pathway for fault-tolerant control of multiphase motors with strong potential for engineering applications.

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Professor Ye Yuan

Mr. Yu Nan

Dr. Fan Yang

Dr. Yizhou Hua

Dr. Shusheng Li

Dr. Weiping Niu

Dr. Zhenzhen Kong

Dr. Xifeng Wang

Dr. Sichao Chen