Comparison between 9-level hybrid asymmetric and conventional multi-level inverters for medium voltage application

A hybrid asymmetric 2-cell 9-level inverter is analysed and compared with two conventional multilevel inverters: the 9-level cascaded H-bridge and the 3-level diode clamped inverter, when used to drive an induction motor of 4.16kV/500kVA. In this analysis, Total Harmonic Distortion (THD), First Order Distortion Factor (DF1), power semiconductor losses, and efficiency are selected as performance indexes. The results indicate that the hybrid asymmetric topology has a better performance in performance indexes than the other topologies which leads to energy saving, better power quality and reduction in size, weight and volume of the LC-filter.