Advanced Multilevel Inverter Design for Grid-Tied PV Systems

Power Renewable energy sources (RES) have gained significant importance in recent decades due to their sustainability, zero emissions, and ease of deployment. Among various RES technologies, photovoltaic (PV) systems are widely utilized owing to their lightweight design, environmental friendliness, and straightforward installation. PV cells inherently generate direct current (DC) electricity, necessitating a suitable power conversion system to transform DC into alternating current (AC) before integration into the power grid. Multilevel inverters (MLIs) are commonly employed for DC-AC conversion in grid-connected renewable energy systems. However, conventional MLI topologies present several limitations. For instance, diode-clamped MLIs require additional diodes alongside active switches, flying capacitor MLIs demand extra capacitors and exhibit complex control challenges as the voltage levels increase, and cascaded H-bridge MLIs necessitate multiple isolated DC sources, restricting their practical application. This paper introduces a novel multilevel inverter topology that achieves DC-AC conversion with a reduced switch count compared to conventional MLIs. The proposed inverter is designed to facilitate seamless PV system integration into the grid while ensuring compliance with key grid parameters such as phase angle synchronization, frequency stability, and voltage amplitude matching. To validate the effectiveness of the proposed topology, seven-level and thirteen-level inverter configurations are modelled and simulated in the MATLAB/Simulink environment, with comprehensive results presented in this study . .Key Words: Grid Integration, Photovoltaic (PV) System, Multilevel Inverter (MLI), Renewable Energy Sources (RES).