Review of Conventional, Intelligent, and Optimization-Based MPPT Techniques for Grid-Connected PV Systems

The rapid integration of photovoltaic (PV) systems into modern power networks has intensified the need for efficient control strategies to ensure maximum power extraction, grid stability, and power quality. Variations in solar irradiance, temperature, and grid conditions significantly affect PV system performance, necessitating advanced Maximum Power Point Tracking (MPPT) and inverter control methods. This paper presents a comprehensive review of conventional, intelligent, and optimization-based control techniques employed in grid-connected PV and hybrid microgrid systems. Various MPPT algorithms, including classical methods, soft computing approaches, and metaheuristic optimization techniques, are critically analyzed with respect to tracking accuracy, convergence speed, computational complexity, and robustness under dynamic conditions. Furthermore, inverter control strategies, synchronization methods, and hierarchical control architectures for microgrids are discussed. A generalized control block diagram is presented to illustrate system integration. Finally, key challenges, research gaps, and future directions are highlighted to guide researchers toward next-generation intelligent and resilient PV-based energy systems.