Optimized carrier based multilevel generated modified dual three-phase open-winding inverter for medium power application

This paper presents a novel carrier based multilevel modulation for modified dual three-phase open-winding inverter applicable for low-voltage/high-current applications. A standard three-phase voltage source inverter (VSI) is connected across the open-winding of both ends of the motor. Each VSI incorporates an additional bi-directional switching device (MOSFET/IGBT) per phase and all three legs link to the neutral of two capacitors in the power circuit. An original optimal double carrier zero-shifted five-level modulation (DCZ SFM) algorithm is also presented and is used to modulate each VSI in a similar way to a 5-level multilevel inverter. The complete model based system is simulated in Matlab/PLECS software's and set of results are presented which shows good conformity with the theoretical analysis.