Single-Phase Open-Circuit Fault-Tolerant Control for a Dual Five-Phase Permanent Magnet Motor With Multioperational Modes

Traditional fault-tolerant strategies inevitably lead to an increase in the amplitude of the fault-tolerant current. In this article, a new fault-tolerant control (FTC) method is proposed for single-phase open-circuit faults in a multioperational mode dual five-phase permanent magnet (MODF-PM) motor. The proposed method takes advantage of the motor structural characteristics to keep the amplitude of the faulty stator phase currents under fault-tolerant conditions the same as that under healthy operation. Two main strategies, termed torque compensation method and flux regulation method, are proposed. On one hand, the $q$ -axis current of the inner stator is used to compensate for the torque loss in the case of outer stator failure. On the other hand, the $d$ -axis current is controlled to enhance the magnetic flux of the outer stator. However, in the case of inner stator failure, since the outer stator does not have the magnetization capacity, only the torque compensation method can be used. By analyzing the structure of the motor, a mathematical model is established and two current distribution modes are provided. Based on the principle of minimum copper loss, the optimal operating mode is selected. Finally, the effectiveness of the proposed method is verified through experiments.