Reduction of dc voltage sources and switches in asymmetrical multilevel converters using a novel topology

This paper presents a novel topology for asymmetrical cascade multilevel converter. The proposed circuit consists of series connected sub-multilevel converters blocks and it can generate more dc voltage levels than other topologies. The proposed topology results in reduction of dc sources and switches number, losses, installation area and converter cost. This converter has been used in a DVR, which has not any coupling transformer. The DVR which is based on the proposed converter has been modeled and the simulation results show its capability in solving power quality problems. The operation and performance of the proposed multilevel converter has been verified by the measurement results of a single-phase 147-level multilevel converter. (c) 2006 Elsevier B.V. All rights reserved.