An 18-Pulse AC-DC Converter-Fed 27-Level Inverter Based Vector Controlled Induction Motor Drive

This paper proposes a method to enhance the power quality of the medium voltage multilevel inverter based induction motor drive system. An 18-pulse AC-DC converter is used to feed a 27-level inverter based vector controlled induction motor drive (VCIMD). Using this configuration, the input supply current distortion decreases to meet the demand of an IEEE-519 standard. The distortion in the 27-level inverter output voltage and its switch cost are decreased impressively with an increase in the number of AC-output voltage levels. As the steps of output voltage are increased, it is switched at low switching frequency. The proposed drive system is examined in the all possible operating conditions of an induction motor. The proposed 18-pulse AC-DC converter fed 27-level inverter for VCIMD is modelled and its performance is simulated in Simulink/MATLAB environment to demonstrate its effectiveness for the medium and large rating applications.