Thirty-six pulse AC-DC converter fed T-type inverter based vector controlled induction motor drive

In this work, a vector controlled induction motor drive (VCIMD) is proposed for the medium and high rating applications. At input end of the proposed drive, a thirty-six pulse AC-DC converter is used to limit the utility current harmonics to acceptable level as specified in IEEE-519 standard. A 5-level T-type multilevel inverter is used at the drive end to improve the steady state, dynamic and power quality performances of VCIMD. To avoid voltage balancing problem at the input of a T-type inverter, the isolated DC supplies are used. These isolated supplies are derived from a delta-polygon configured phase shifting transformer followed by six pulse diode bridge rectifiers (DBRs). In order to control a T-type inverter and an induction motor, the simple phase disposition (PD) sinusoidal pulse width modulation (SPWM) and the indirect vector control are used, respectively. The proposed drive is examined under all possible operations of an induction motor. The proposed thirty-six pulse AC-DC converter fed 5-level T-type inverter based VCIMD is modelled and its performance is simulated in Simulink/MATLAB environment to demonstrate its effectiveness for the medium and high rating applications.