Impact analysis of capacitive energy storage integration on load frequency control performance of microgrids employing a new dual-stage controller

Abstract

A microgrid (MG) with inherent low inertia and renewable energy sources (RES)-based generators may encounter difficulties in maintaining frequency stability due to load changes. In order to mitigate frequency stability concerns, it is imperative to use energy storage units (ESUs). Objective of this study is to analyze the impact of capacitive energy storage unit (CESU) integration on the load frequency control (LFC) performance of two distinct MG systems. A new dual-stage ${\mathrm{PI}}^{\lambda }-(1+{\mathrm{PD}}^{\mu }F)$ controller is proposed as a secondary controller for the LFC study. Parameters of the controller are optimized employing a recently developed arithmetic optimization algorithm (AOA). Performance of the suggested control approach is evaluated against several standard control approaches. Simulation findings demonstrate that with CESU integration the suggested controller markedly enhances frequency and tie-line power deviation responses and their transient characteristics for both the MG systems. A maximum improvement of 98.50% in peak overshoot, 94.88% in peak undershoot, and 77.18% in settling time is observed with the suggested control approach. This study further justifies the robustness of the proposed control approach against the MG systems parameter variations, impact of CESU integration through statistical analysis, small signal stability of both the MG systems, and convergence performance of the AOA.