Simplified SVPWM-DTC of 3-phase induction motor using the concept of imaginary switching times

This paper presents a new space vector pulse width modulation based direct torque control technique for three-phase induction motor drive using concept of imaginary switching times. The effective time is determined using imaginary time vector there by the lengthy procedure of using reference voltage vector is eliminated. Also the sector identification and angle determination are not used. Simulation studies have been carried out for the proposed method and results are compared with basic DTC. Results show that the torque, current and flux waveforms are superior to that of conventional direct torque control technique. Though the results of the proposed method are at par to those of DTC with conventional space vector pulse width modulation, there is a significant reduction in execution time due to elimination of lookup table and simplicity in algorithm.

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