A comparative analysis of power pulsating buffer architectures for mitigating high-frequency and low-frequency ripple in PV microinverter applications

This study provides a comparative analysis of feasible architectures of Power Pulsating Buffer (PPB) as an actively controlled energy storage solution alternative to the electrolytic capacitors in a single-stage isolated, single-phase 120 V AC 60Hz grid-connected photovoltaic (PV) microinverter for a 400 W rated system with 20–40 V input range. The comparison encompasses key factors including energy density, volume reduction, efficiency, frequency operation, and system stability. The findings shed light on the primary advantages and disadvantages of the buck- and boost-derived PPB under study. The results indicate that the boost PPB exhibits enhanced stability, a more compact design, and higher power efficiency compared to the buck PPB. However, for low switching frequency operations, the buck PPB proves to be more effective in mitigating DC port voltage ripple and ensuring controller over microinverter load variation.