A Torque Ripple Minimization Scheme in Direct Torque Control of Induction Motors

One of the disadvantages of conventional direct torque control (DTC) is high torque ripple. Applying duty ratio control technology can effectively reduce the torque ripple. In this paper, a new duty ratio control technology using PI controller is presented. The proposed PI controller has two inputs: actual torque value and reference torque value. Its output is the duty ratio of a voltage vector. Simulation results show that a great reduction of torque ripple is achieved, and the algorithm is simple and easy to implement.