Implementation and Control Different Multilevel Inverter Topologies for Current Waveform Improvement
Multilevel converters offer advantages in terms of the output waveform quality due to the increased number of levels used in the output voltage modulation. This advantage is particularly true for Cascade H-Bridge (CHB) converters that can be built to produce a large number of levels owing to their modular structure. In this paper, the NPC connected with the H-Bridges (HBs) is used for improving the voltage waveform quality. Further more, NPC converter can be replaced with flying capacitors to get an improved output current waveform. This topology requires only a main dc-link voltage and presents a easy way to increase the output voltage levels by increasing the number of cells.