Efficient Load Frequency Regulation of Islanded Microgrids with Fractional-Order PI Controller

This article focuses on load frequency regulation of islanded microgrid <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$(I\mu \mathbf{G})$</tex>, which consists of various distributed generation sources like photovoltaic cells, wind turbines, microturbine, biodiesel engine generators, and biogas turbine generators with energy storage systems such as the battery, flywheel, ultracapacitor, and electric vehicles. To eliminate undesirable frequency deviations and errors of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$(I\mu \mathbf{G})$</tex>, a fractional-order proportional-integral (FOPI) controller is utilized. Fine-tuning of FOPI controller gains is performed through a rule-based method. To prove the efficacy of FOPI controller in stabilizing frequency response, various simulation-based studies are conducted and compared. Moreover, comparative frequency response, with and without controller and transient specifications, underscore the importance of FOPI controller in stabilizing microgrid frequency.