Coordination strategies of distributed energy resources including FESS, DEG, FC and WTG in load frequency control (LFC) scheme of hybrid isolated micro-grid

摘要

This paper presents a novel load frequency control (LFC) model for a stand-alone hybrid micro-grid in the presence of renewable energy resources. A perilous fact in operation of isolated micro-grid is to deal with a low-inertia system owing to the unpredictable structure and the intermittent fluctuation of RESs. In comparison to the conventional power system, the rate of change of frequency (RoCoF) is high in isolated micro-gird. Therefore, the need for fast frequency response provision delivered by existing distributed energy resources, which are inverter-connected technologies, arises. Some distributed energy resources (DERs) can be considered as potential reserves for active power injection in the load frequency control scheme. The simulation results depict that renewable energy resources like diesel engine generator (DEG), Fuel Cell (FC), Flywheel Energy Storage System (FESS) and Wind Turbine Generator (WTG) have the capability to improve frequency excursion during various operating conditions if comprehensive small-signal dynamic models for RESs are introduced in isolated micro-grid and proper contribution of them in load frequency control studies is considered.