Multilevel DC-AC converters for renewable power generation plants: Comparison, simulation, and experimental tests

Hybrid generation plants are attractive only if they work with a high reliability, low assembling and maintenance costs, and very low environmental pollution. Actually, this is possible only if a proper power interface between the sources and the load is used. Main task of this work is to identify DC/AC multilevel inverter topologies, which can properly operate in hybrid production plants. Actually, several multilevel converter circuits have been studied in literature, but only a few of them have been experimentally tested. This paper shows an analysis of different multilevel inverter topologies along with their control techniques. The identification of the more suitable solutions for a given hybrid plant configuration has been made through computer simulations and the most promising circuit has been designed for experimental tests. The converter electrical parameters such as efficiency, output voltage THD and energy losses have been checked by means of accurate computer simulations.