Due to the lack of inertia and uncertainty in the selection of optimal Proportional Integral (PI) controller gains, the voltage and frequency variations are higher in the islanded mode of the operation of a Microgrid (MG) compared to the grid-connected mode. This study, as such, develops an optimal control strategy for the voltage and frequency regulation of Photovoltaic (PV) based MG systems operating in islanding mode using Grasshopper Optimization Algorithm (GOA). The intelligence of the GOA is utilized to optimize the PI controller parameters. This ensures an enhanced dynamic response and power quality of the studied MG system during Distributed Generators (DG) insertion and load change conditions. A droop control is also employed within the control architecture, alongside the voltage and current control loops, as a power-sharing controller. In order to validate the performance of the proposed control architecture, its effectiveness in regulating MG voltage, frequency, and power quality is compared with the precedent Artificial Intelligence (AI) based control architectures for the same control objectives. The effectiveness of the proposed GOA based parameter selection method is also validated by analyzing its performance with respect to the improved transient response and power quality of the studied MG system in comparison with that of the Particle Swarm Optimization (PSO) and Whales Optimization Algorithm (WOA) based parameter selection methods. The simulation results establish that the GOA provides a faster and better solution than PSO and WOA which resulted in a minimum voltage and frequency overshoot with minimum output current and Total Harmonic Distortion (THD).

Summary Microgrid implementation requires effective and efficient strategies for controlling the grid parameters. Various problems are encountered with the deployment of distributed generation in terms of reverse power, an imbalance between power generation and nonlinear load. This paper is focused on the existing controllers in terms of their merits and limitations. Furthermore, the state of the art of the local power distribution system especially on renewable energy resources along with energy storage methods is explored. Reliability and stability of power flow between sources and consumers via voltage source inverter are also considered. The emerging microgrid concept in islanding and grid‐connected mode using different controller along with soft computing algorithm are presented. This paper gives the reader fast insight into the context of the controller and its application.

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