Cascade-multi-cell multilevel converter with reduced number of switches

Recently applications of multilevel converters have been pointed out because of some advantages include high-quality output waveform, reduced harmonic distortion and lower electromagnetic interference. However, some drawbacks such as increased number of components like switches and dc power supplies and complex pulse width modulation control method are associated with these converters. In this study, a new cascade multilevel converter is introduced named ‘cascade-multi-cell’ converter. First, the basic constitutive of the proposed multilevel converter has been explained. Then, symmetric and asymmetric configurations are presented. The number of switches and gate driver circuits in the proposed structure are less than the conventional cascade converter. Therefore its output voltage levels will be increased. Also, the number of on-state switches is reduced in presented topology, and so the conductive losses will be reduced. The peak inverse voltage of the proposed converter is equal with the traditional cascade converter. Finally, simulation and experimental results are presented. The presented results show the validity and effectiveness of the proposed multilevel structure.