Design of a High-Efficiency Single-Stage Series Resonant Micro-Inverter

Inhalt:
This paper shares the design of a high-efficiency single-stage series resonant micro inverter used for domestic photovoltaic (PV) systems. The First Harmonic Analysis (FHA) model of the system is first established. An analytical modulation scheme of small root-mean-square resonant current, reliable full-range Zero Voltage Switching (ZVS), and small switching frequency variation range is proposed. Design indexes are proposed to further guide the selection of hardware parameters. By calculating the CEC weighted average of different indexes under different hardware parameters, the optimal hardware parameters are selected for optimal design. A loss estimation is conducted accordingly. Finally, a prototype is built and experimentally verified, exhibiting a peak efficiency of 96.23%, a CEC efficiency of 95.12%, and a power density of 34W/in3.