Multilevel Dodecagonal Space Vector Generation Using Stacked Inverter Cells for IM drives

This paper proposes a new induction motor drive scheme to generate a dense multilevel dodecagonal space vector structure, by stacking two 3-level flying capacitors and cascading two H-bridges. The proposed scheme combines the benefits of both multilevel as well as dodecagonal voltage space vector structure. All the capacitors in the stacked inverters are balanced using switching state redundancies within a sampling period. The H-bridges act as a harmonics filter and provide only reactive power, irrespective of load power factor and the capacitors are naturally balanced. The stacked inverter operates in quasi square wave mode throughout the modulation range and results in less switching losses. Both the simulation and experimental results are included in the paper to support the effectiveness of the proposed scheme