Enhancing Fault-Tolerant Ability of a Nine-Phase Induction Motor Drive System Using Fuzzy Logic Current Controllers

With distinct advantages over three-phase machines, multiphase machines are gaining increasing popularity in ship electric propulsion applications. Many fault-tolerant control strategies have been proposed for multiphase drive to suppress the torque ripples under faulty conditions; however, most of them depend heavily on the mathematical models and the need of the prefault to postfault transitions, which would increase the complexity of the control system. Because of high robustness, Fuzzy Logic controllers are suggested to substitute the proportion integration (PI) controllers in the current loops of rotor-flux oriented control (RFOC) for multiphase induction motors in this paper. The experimental results from a multiphase drive platform demonstrate that compared with the conventional RFOC with PI current controllers, Fuzzy logic-RFOC has significantly improved the fault-tolerant ability of the nine-phase drive system in various kinds of faulty conditions.