Firefly-optimized PI and PR controlled single-phase grid-linked solar PV system to mitigate the power quality and to improve the efficiency of the system

The study evaluates the performance of an inverter control in a single-phase grid-linked PV scheme, focusing on addressing issues like transient response, voltage overshoot, harmonics and steady-state error. The objective of this work is to optimize the gain parameter of the PI voltage and PR current controller in grid-connected PV system to enhance power quality and system stability by stabilizing DC link voltage, grid frequency, reducing the harmonics of the grid current. The Firefly Algorithm used in this work to optimize the PI and PR controller gain value in grid-connected PV system and compared with Trial and Error, Ziegler-Nichols, and particle swarm optimization, ant colony optimization, Bat Algorithm, Jaya algorithm, and Hippopotamus Optimization Algorithms. Experimental validation in MATLAB shows the firefly algorithm achieves the best results in terms of rise time (20 ms), overshoot (2%), settling time (160 ms), current THD (3.76%), and efficiency (98%). This approach significantly enhances power quality in grid, facilitating easier integration of PV systems into the utility grid.