Comparative analysis of PSC-SPWM and NLM in modular multilevel converters

Modular Multilevel Converter is very popular converter topology in high-power applications due to its several advantages. For MMCs, selection of a modulation technique impacts the overall efficiency of converter in terms of harmonic distortion. Therefore, understanding specific criteria of each modulation technique is crucial for optimizing MMC operation. This study compares two modulation techniques, Phase-Shifted Carrier SPWM and Nearest Level Modulation (NLM) to determine the more effective method in reducing total Harmonic Distortion in MMC converters. The comparative analysis is taken across varying submodule configurations of MMC on MATLAB/Simulink to evaluate the harmonic content generated by each method. The results provide suitability of PSC-SPWM and NLM techniques for reducing THD in MMC at varying submodule configurations which is useful for engineers and researchers in selecting the most effective modulation technique based on the specific requirement of converter.