DC/AC Power Converters for Hybrid Renewable Energy-Based Applications

Abstract

In DC-AC power conversion, multilevel inverters (MLIs) are getting more attention in the medium range of voltage and power applications such as flexible alternating current transmission systems (FACTS), high voltage direct current (HVDC) transmission systems, high power machine drives, and renewable energy sources. Improved spectral performance, reduced electromagnetic interference (EMI) with neighboring circuits, lower blocking voltage on the devices, and reduced size of the filter are some of the advantages of MLIs. With these motivating factors, contemporary research is focused on synthesizing hybrid topologies for power converters with a fewer number of power devices and higher efficiency. Present day industries employ high-power, medium voltage equipment (at mega-watt level with 2.3–6.9 kV). In order to cope up with these requirements, a new family of multilevel converters has emerged which combines MLIs and hybrid topologies. This chapter primarily focuses on the derivation of hybrid multilevel inverter (HMLI) topologies for medium voltage applications. A comprehensive review on HMLI topologies have be presented based on the component count, voltage stress, merits and demerits. Further different recently proposed HMLI topologies and its significances have been addressed with simulation results. Finally concluding comments and future directions of research on HMLI topologies are presented.