Six-Phase Worm Drive Motor Design with Fault – Tolerant Control

With the continuous development of industrial technology, multi-phase motors are widely used in fields such as industrial robots, ships, and automobiles. The performance requirements for motors are increasing, making their integration and reliability particularly important. To address the issues of low integration and the need for additional braking devices in traditional externally-driven reducers, this paper designs a six-phase fault-tolerant motor based on a built-in drum-shaped worm reducer, integrating worm drive with the six-phase fault-tolerant motor to achieve drive, control, and transmission as a unified system. This study focuses on the fault-tolerant control strategies for a six-phase permanent magnet synchronous motor (PMSM) under a single-phase open-circuit fault. Based on the principle of constant total magnetomotive force, two fault-tolerant control methods: minimum current and maximum output torque are proposed. The effectiveness and stability of these strategies in maintaining stable operation under rated load after a phase-loss fault are verified through MATLAB/Simulink simulations and prototype experiments.