Load frequency control in a standalone microgrid: A novel fractional order tilt multilevel PIDF control approach

• A novel FOTMLPIDF controller is proposed to improve the frequency response of autonomous MG. The recommended FOTMLPIDF controller procures the merits of multilevel PID controllers, tilt and fractional order controllers in one controller setup. • QIO algorithm adopted to optimize the FOTMLPIDF controller and supremacy of QIO authenticated over recent optimization techniques. • Efforts have been made to address all the LFC specifications as outlined in literature. The proposed controller has been compared with various controllers from existing studies, including recent controllers such as MLPIDF, TPIDF and PIDF controllers. • Lastly, the robustness of suggested FOTMLPIDF controller is extended to cyber attacks, ESS disconnection, MG uncertainties and renewable intermittencies in a single controller framework. In a standalone microgrid (MG), with intermittent output power from renewable energy sources, communication delays, low system inertia, parametric uncertainties, and load changes cause power imbalances in the MG. The uncontrolled power imbalances can lead to significant frequency deviations and thereby a blackout. PID controllers usually address these problems, but they may not completely resolve the dynamic requirements of modern MG. This paper proposes a novel fractional order tilt multilevel PID controller with filter (FOTMLPIDF) to enhance the frequency response of the MG. In this method, the proposed approach coordinates diesel engine generators (DEGs) and fuel cells (FCs) to manage the MG frequency effectively. The proposed controller parameters are optimized effectively through the use of a recently developed Quadratic Interpolation Optimization (QIO) algorithm. Various disturbance scenarios are accounted for to assess the performance of the suggested controller. The simulation results substantiate that the recommended controller attains improved dynamics compared to advanced controllers in the literature, including MLPIDF, TPIDF, and PIDF controllers. Up to 50% of renewable penetration, the overall frequency error is reduced by 60%, 87% and 95% respectively. Besides that, the suggested controller is more robust to parametric variations and cyber attacks.