An Adaptive Droop Control Strategy for Frequency Restoration in an AC Islanded Microgrid
DOI:
https://doi.org/10.12928/biste.v8i4.16077Keywords:
Camel Algorithm, Droop Control, Islanded Microgrid, Distributed Generator, MATLAB/SimulinkAbstract
Recently, industrial sectors have become more and more enthusiastic about microgrid solutions. Most of these microgrids are based on using green and renewable energy sources. Such microgrids can either be connected to the main utility grid for purposes like cost savings, or they can be standalone independent island microgrids. Typically, microgrid control systems employ a three-layer method: primary, secondary, and tertiary. One major issue for islanded microgrids is that they lack a reference point for voltage and frequency since they are not connected to the utility grid. The Camel Algorithm (CA) is an optimization method inspired by nature that imitates how camels adapt and travel in desert environments. This paper applies the CA to adjust the active power droop coefficient dynamically in real time. The case scenario is a microgrid powered by a three distributed generator (DG) AC Island capable of standing alone with an actively varying load from 5 kW to 10 kW through unequal feeder impedances. Simulation results indicate that the proposed controller can maintain the microgrid frequency in a narrow range of 49.95-50 Hz, with a settling time of about 0.22 s. Moreover, the proposed method improves the active power-sharing dynamics and significantly reduces frequency deviations compared to the conventional fixed-droop control schemes.
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