New Active Stacked NPC Multilevel Converter: Operation and Features

In this paper, the operation and the features of a new three-level converter are presented. The proposed topology was named three-level active-stacked neutral point clamped (3L-ASNPC). It is a derivative of the 3L-SNPC structure, having two additional active switches connected antiparallel with the clamp diodes. The main advantage of 3L-ASNPC converter is the reduction of the average switching frequency for all power devices. In the same time, the apparent switching frequency of the output voltage is doubled. Experimental and simulation results are shown in order to validate the proposed structure and the analysis of the switching states.