Design, Implementation, and Performance Analysis of a High-Efficiency Single-Stage Inverter Architecture with Integrated Battery Storage for On-Grid and Off-Grid Solar PV Applications

This paper introduces a single-stage solar inverter design that seamlessly integrates battery-based energy storage for both on-grid and off-grid scenarios. The proposed approach aims to reduce system complexity by employing a single power-conversion stage that provides step-up functionality for the photovoltaic (PV) array and a controlled AC output for local loads or the utility grid. A centralized microcontroller-based logic dynamically balances maximum power point tracking (MPPT) from the PV array with selective battery charging or discharging, ensuring high energy utilization, stable operation, and minimal active-power curtailment. Additionally, the inverter supports evolving grid requirements, including ride-through capabilities and reactive power control for voltage regulation. Hardware-level modifications, such as wide-bandgap transistors and carefully tuned output filters, enhance conversion efficiency-reaching approximately $93 \%$ at nominal load-while maintaining a low total harmonic distortion (THD). Simulation and experimental assessments confirm that the system can adapt to rapid changes in irradiance and demand, making it suitable for both residential and small commercial PV installations.