Different switching patterns in DTC of IM

Direct torque control (DTC) technique is used for induction motor (IM) control. Due to the high switching frequency, nonpulse width modulation (NPWM) techniques are frequently preferred. Four different switching algorithms using hysteresis and nonhysteresis controllers are proposed and compared. Drive with torque reference, with speed reference in steady-state and dynamic modes are controlled using four different switching techniques. Also, the harmonic spectra of the stator voltage and current are determined and compared in the above techniques. Among these algorithms, the nonhysteresis controllers called two-band flux controller and triple-band torque controller lead to a better result with an advantage of simpler control algorithms