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This paper presents a torque ripple reduction method of direct torque control (DTC) using fuzzy controller with optimal selection

strategy of voltage vectors in a five-phase induction motor. The conventional DTC method has some drawbacks. First, switching

frequency changes according to the hysteresis bands and motor’s speed. Second, the torque ripple is rapidly increased in long

control period. In order to solve these problems, some/most papers have proposed torque ripple reduction methods by using the

optimal duty ratio of the non-zero voltage vector. However, these methods are complicated in accordance with the parameter. If

this drawback is eliminated, the torque ripple can be reduced compared with conventional method. In addition, the DTC can be

simply controlled without the use of the parameter. Therefore, the proposed algorithm is changing the voltage vector insertion

time by using the designed fuzzy controller. Also, the optimized voltage vector selection method is used in accordance with the

torque error. Simulation and experimental results show effectiveness of the proposed control algorithm.