Microgrid Control Techniques : A Review

Microgrids (MGs) are localized energy systems that integrate distributed energy resources (DERs),including renewable energysources, energy storage systems (ESS), and conventional power generation sources. A critical challenge in operatingmicrogrids is maintaining frequency stability, particularly during transient disturbances or load imbalances. This review provides a comprehensive analysis of various frequency control strategies employed in microgrids to ensure stable and reliable operation. The paper categorizes existing approaches into primary, secondary, and tertiary frequency control methods, evaluating their mechanisms, advantages, and limitations. Primary control focuses on immediate frequency regulation through local droop control, while secondary control ensures the restoration of frequency to its nominal value through centralized or decentralized coordination. Tertiary control manages economic dispatch and energy optimization for long-term stability. The paper further highlighted emerging technologies in the field of microgrid control. Additionally, the review examines the impact of DER characteristics, including variability and intermittency, on frequency regulation.It discusses advanced techniques, including model predictive control, fuzzy logic control, and Neural network control. The paper concludes with a discussion on future trends in microgrid frequency control, emphasizing the need for robust encryption and intrusion detection systems that protect microgrid control networks from cyber threats, ensuring reliable frequency regulation even in the event of a cyber-attack.