Development of Systems Dedicated to the Integration of Renewable Energy Sources into the Electrical Grid

Abstract

This thesis focuses on the design, modeling, and development of systems dedicated to the integration of renewable energy sources, primarily photovoltaic (PV) and wind energy, into the electrical grid. The growing global reliance on clean energy has brought significant attention to the technical challenges posed by the intermittent and decentralized nature of renewable sources, especially in terms of grid stability, power quality, and synchronization. To address these issues, the research proposes advanced control strategies and system architectures that ensure reliable and efficient energy conversion and delivery. The study includes detailed modeling of PV and wind subsystems, the implementation of maximum power point tracking (MPPT) algorithms, and the design of multi-level inverter topologies for single- stage and hybrid configurations. Emphasis is placed on grid synchronization through advanced techniques such as the Synchronous Reference Frame (SRF) control and the Dual Second Order Generalized Integrator Phase-Locked Loop (DSOGI-PLL). Simulations are carried out using MATLAB/Simulink to validate system performance under varying environmental and grid conditions. The results demonstrate effective voltage and frequency regulation, reduced total harmonic distortion (THD), and dynamic power balancing, confirming the robustness of the proposed solutions. This work contributes to the development of intelligent and scalable renewable energy integration systems, in line with smart grid requirements and sustainable energy goals. It offers a practical foundation for future renewable-based grid systems, with potential extensions to storage integration and energy management