Multi-objective modulation scheme development for optimal control of Cascaded H-Bridge (CHB) multilevel inverters

The problem is defined as seeking optimal operating parameters for a Cascaded H-bridge (CHB) converter under multi-objective scenarios. An advanced modulation technique is considered to address the non-ideal situations where dc-link voltage ripples are present. Higher quality waveforms are achievable by adding to the optimization degree of freedom with more number of decision variables. DC offset value (V-{offset} and chopping or switching frequency (f-{chop}) are added as additional variables, alongside dc-link voltage levels and firing angles, to be optimally determined as modulation parameters. This study examines indices such as f-{chop}, weighted total harmonic distortion (WTHD), and deviation rate (DR) to obtain a systematic platform for specific design priorities. An improved converter performance with reduced switching loss, suppressed harmonic content, and resilience against dc-link ripples is of key concern in this study.