IEEE Journal of Emerging and Selected Topics in Power Electronics | 2021
Voltage and Current THD Minimization of a Single-phase Multilevel Inverter with an Arbitrary RL-load Using a Time-domain Approach
Abstract
This paper presents a time-domain optimization technique for minimizing harmonic content in the output voltage and current waveforms of a single-phase multilevel inverter topology with arbitrary RL-load. The effect of modulation index and load parameters variation on the harmonic content of load voltage and current have also been analyzed. A single-phase 21-level multilevel inverter is developed to verify the proposed switching technique. The total harmonic distortion of the current and voltage in the time-domain is considered as the optimization constraint to compute the inverter’s optimal switching angles. In addition, the load time constant has also been considered during optimization problem formulation, which enables superior inverter performance in terms of lower THD in the output response. The detailed theoretical, simulation and experimental analysis are carried out on the presented topology to verify the proposed switching technique’s performance.