An Expeditious Frequency Stabilization in a Microgrid using Fractional Order Controller

This paper assesses the frequency stability of a microgrid (MG) assisting a fractional-based two-stage controller with a derivative filter. Here, the integrated distributed generators (DGs) in the MG are solar power extraction unit, wind power extraction generator, diesel generator, microturbine generator, fuel cell, flywheel, and battery storage unit. Out of these DGs, some sources are low inertia generators, some sources have no inertia, and some sources produce variable power. So, all these issues create frequency control problems in the MG. To overcome this control challenge, a fractional-order proportional-integral (FOPI) controller is integrated with an FO-proportional-derivative (FOPDN) controller coordinated by a filter named FOPI-PDN controller that is used as a secondary controller. The proposed controller is designed by Wild Goat Algorithm (WGA) algorithm. Simultaneously the performance of the FOPI-PDN controller is validated by comparing it with the performance of PID and FOPID controllers. Further, the stability of the frequency is observed by injecting variable load and variable power generated by wind and solar systems, which approves the robustness of the FOPI-PDN controller.