Boosting Frequency Stability in Multi-Microgrid Systems With an Innovative Dual-Hybrid Fractional Control Scheme Integrating Demand Response

Abstract

Modern electrical power grids are characterized by a significant increase in renewable energy generation, often complemented by energy storage systems. Integrating these storage devices helps to offset the challenges posed by the decreased system inertia resulting from high levels of renewable energy penetration. However, the limited capacity of these storage units, attributed to their high costs, necessitates incorporating controlled loads such as high voltage air conditioning (HVAC), compressors, chillers, or pumps to enhance frequency stability through demand response (DR). This paper proposes a novel control scheme containing a dual-hybrid fractional controller for load frequency control (LFC) and DR. The structure of this control scheme comprises two components, each utilizing fractional order tilt-integral-derivative alongside a fractional filter termed D-Hyd controller. One component handles the LFC through the area control error (ACE) signal, and the other handles the DR through the area frequency deviation. Moreover, a new application of the exponential distribution optimization (EDO) algorithm is developed to determine the parameters of the proposed controllers concurrently. The effectiveness of the proposed approach is evaluated through case studies involving two interconnected areas with photovoltaic and wind energy sources. Various test scenarios and comparisons with existing methods in the literature are presented to assess the performance of the proposed controller and optimization algorithm. Moreover, practical uncertainties are considered in the test scenarios to evaluate the stability and robustness of the proposed schemes. Compared to recent control methods in the literature, the proposed control scheme offers more flexibility and resiliency in preserving system stability.