Modified SPWM technique for improved harmonic performance of single PV array fed grid‐tied five‐level converter

Abstract

This study presents a performance assessment of a single photovoltaic (PV) array fed transformer-based five-level converter topology with optimal shift factor-based modified sinusoidal pulse width modulation (OSF-MSPWM) technique under a dynamic solar PV environment. The five-level converter output is generated using H bridge cells and single-phase transformers. A single PV array is fed to all cascaded H bridge cells and isolation is provided by cascading secondary windings of the transformers in the AC side. The separate DC sources requirement is eliminated and galvanic isolation is provided by single-phase transformers. The decoupled controller with modified in-phase disposition PWM technique is used for active power injection into the grid at unity power factor. This work uses a new carrier shape at the same input carrier frequency and modulation index m f for improving the harmonics performance of the five-level converter. Hence, shift the dominant harmonics to the higher side for developed topology and performing optimal shift factor-based modulation is compared with the conventional SPWM technique. The steady-state and dynamic responses of the PV multilevel converter are observed in MATLAB simulation and tested in a real-time platform.