Comprehensive modeling of single-phase quasi-Z-source photovoltaic inverter to investigate low-frequency voltage and current ripples

摘要

The double-line-frequency (2ω) power ripple of single-phase quasi-Z-source (qZS) Photovoltaic (PV) inverter highly affects the whole system's design and performance. In this paper, a comprehensive modeling for single-phase qZS PV inverter is proposed, where the 2ω-ripple models of qZS inverter system served by real PV source are established and discussed on cases of with and without PV terminal capacitor. The influences from qZS inductance and capacitance, as well as PV panel terminal capacitance to the 2ω ripples are investigated by using the built models. Simulation and experimental results validate the proposed comprehensive 2ω-ripple models for the qZS-PV inverter.