Extended high step-up structure for multilevel converter

This study presents a new high step-up multilevel converter topology. The proposed multilevel converter comprises of two dc voltage sources, several capacitors, unidirectional switches, and power diodes. The proposed topology can increase the values of input dc voltage sources substantially. The voltage gain of the proposed topology depends on the number of used capacitors. The proposed topology is simple and can be extended to produce higher-output voltage levels. The values of two used dc voltage sources can be selected as symmetric and asymmetric. In symmetric type, the values of two dc sources are similar. However, the dc sources magnitudes in asymmetric type are unequal and their values are obtained based on mathematical method. Inherent voltage balancing of used capacitors is an important feature of the proposed topology. The proposed topology is compared with other recently proposed high step-up multilevel converters and conventional topologies in terms of the number of used switches, capacitors, dc sources, and voltage on switches. It is indicated that the proposed structure requires the least number of devices and the voltage rating on power switches is low. The performance of the proposed topology and theoretical analysis are confirmed using experimental works.