Delay-Interactive Hierarchical ADRC for Robust Frequency Regulation in Intertied Microgrids

Microgrids are increasingly deployed in modern power systems, yet challenges remain in load frequency regulation (LFR) for intertied microgrids (IμS), especially under the variability of renewable energy sources (RESs) and communication delays. Frequency regulation of renewable sources (wind-PV aggregation) and energy storage integrated two-area IμS has been addressed in this paper. Firstly, a delay interactive tilt-integrated active disturbance rejection controller DI(TI-ADRC) for secondary frequency control, where the explicitly designed controller also incorporates the effects of communication delays encountered during the transmission of control signals. Secondly, given that the performance of the control scheme relies on the optimal configuration of the proposed controller, a novel quasi-oppositional beetle swarm optimization (QOBSO) has been developed to achieve this objective. Additionally, to further improve the response profile, an accurate inertia emulated precise direct current (IEPDC) link in comparison with conventional DC link is developed. The effectiveness of the proposed control strategy is ascertained under real-time load variations and RES intermittency, with stability analysis and performance comparison against recent existing methods to substantiate its supremacy. The quantitative impact analysis, amid pre and post IEPDC tie-link, reveals a significant reduction in maximum frequency overshoot 54.14% and 65.80% for tie-link power exchange compared to the conventional DC link model demonstrating the effectiveness of the proposed approach. Furthermore, the impact of communication delays, modeled using network simulators for various wide area network (WAN) technologies, are also investigated. Real-time simulations on OPAL-RT 5700 confirm the effectiveness of the proposed approach in achieving robust frequency regulation and stability in IμS.