Stability Enhancement of a Multi-Source Interconnected Power System Using a Dung Beetle Optimizer-Tuned PIλDμ Controller

Maintaining frequency stability in modern interconnected power systems (PSs) has become increasingly challenging due to the high penetration of renewable energy sources (RESs) and the dynamic nature of generation and demand. To address these issues, this paper proposes a novel load frequency control strategy that integrates a Dung Beetle Optimizer (DBO)-tuned fractional-order Proportional–Integral–Derivative (FOPID) controller with a newly developed multi-source interconnected power system. This model combines PV, thermal, hydro, nuclear, and advanced storage (HAE and fuel cells). Unlike existing methods, the proposed approach simultaneously leverages DBO’s balanced search mechanism and FOPID’s fractional dynamics to enhance frequency stability under high renewable penetration. The performance of the proposed controller is validated through a comparative analysis with Ant Lion Optimizer (ALO) and Particle Swarm Optimization (PSO) methods. Simulation results show that the DBO-based controller significantly improves dynamic response, achieving reductions in settling time of 9.5% and 4.7% compared to PSO and ALO, respectively. Furthermore, the proposed approach enhances frequency regulation and tie-line power stability over other optimization methods and controllers, demonstrating strong robustness and adaptability for future high-RES power systems.