Yahya Naderi - Faculty of Electrical and Computer Engineering, Tabriz University, Tabriz, Iran
Seied Hossein Hosseini
Arash Mahari
Roya Naderi - Islamic Azad University, Heris Branch, Electrical Department, Heris, Iran

In this paper the Imperialistic competition algorithm (ICA) is used to minimize harmonic components of the output voltage up to 75th harmonic in a multilevel inverterstructure with unequal DC sources by the means of selected switching angles. As the number of switching angles increase,it becomes more difficult to calculate the optimum switchingangles in order to minimize THD, so the ICA method is used to find the global optimum of the search space. In addition,the topology used in this multilevel converter is an optimum topology with maximum number of output voltage steps while the number of switches is constant

Cascaded Multilevel Converter – Multiple DC-Sources — Selective Harmonic Elimination (SHE) –––Triple Switching-Imperialistic Competition Algorithm (ICA)