Integration of Multi-Inverter PV Systems into the Grid Using Five-Level Inverters and MPPT Control

This paper presents the comprehensive modeling, simulation, and analysis of a grid-connected photovoltaic (PV) system consisting of three independent ۳۰۰ W units. Each subsystem integrates a PV array, a DC-DC boost converter with maximum power point tracking (MPPT), and a five-level IGBT-based inverter. The main challenges addressed are reliable synchronization among multiple inverters and their seamless integration with the utility grid while maintaining stable and high-quality operation. A control framework combining dq۰ transformation with active/reactive (P-Q) power regulation was implemented to achieve phase coherency, sinusoidal current injection, and near-unity power factor. Simulation results in MATLAB/Simulink confirm that the proposed system ensures accurate MPPT performance under irradiance variations, eliminates circulating currents caused by inverter phase mismatch, and enhances the overall waveform quality compared with conventional approaches. The modular nature of the proposed architecture enables scalability for larger PV plants and microgrids, where synchronization and power quality are critical requirements. The findings establish a foundation for future experimental validation through hardware-in-the-loop (HIL) testing and the integration of advanced control strategies such as model predictive, fractional-order, and grid-forming approaches.

کلیدواژه ها:

Multi-inverter PV systems ، five-level inverter ، MPPT ، synchronization ، power quality ، grid integration