Comparative Analysis of 51-level Hybrid Multilevel Inverter and 57-level Switched-capacitor Boost Multilevel Inverter

The invention of hybrid multilevel inverters (HMI) and switched-capacitor boost multilevel inverters (SCBMI) has revolutionized power electronic systems by enabling the generation of extremely high AC voltage-level using asymmetrical DC configurations. This paper presents the comparison of the 51-level HMI and 57-level SCBMI topologies in terms of the total number of components and the total harmonic distortion (THD) across different modulation indices (i.e., 0.2, 0.4, 0.6, 0.8, and 1). In addition, the effective switching frequency and the fundamental frequency component of the AC voltage waveforms were also compared. Both the presented inverter topologies were driven by the nearest level control (NLC) modulation technique under one resistive-inductive RL loading condition. MATLAB Simulink simulation studies are utilized to validate the theoretical study of the differences between the topologies.