Hybrid multilevel inverter system for Open-End Winding (OEW) induction motor drive based on Double-Star Chopper-Cells (DSCC) converter

This paper proposes a hybrid multilevel topology for Open-End stator Winding (OEW) induction motor drive based on Modular Multilevel Cascade Inverter (MMCI) with Double-Star Chopper-Cells (DSCC) and 2-Level Voltage Source Inverter (2L-VSI). An efficient Voltage Reference Technique is proposed to generate the pole voltages of both inverters. As a result, the DSCC inverter is commanded in high-switching frequency, while the 2L-VSI operates at the fundamental frequency. A voltage-balancing control of the floating DC capacitors of the DSCC is presented to ensure the energy balance. At last, to investigate the proposed system and control strategy, experimental results are presented.