An Innovative Controller for Improvement of Voltage Fluctuations Following Huge Disturbances in an Autonomous Microgrid

An Innovative Controller for Improvement of Voltage Fluctuations Following Huge Disturbances in an Autonomous Microgrid

Islanded MicroGrids (MGs) are autonomous low voltage distribution systems comprising distributed energy sources, storage devices and controllable loads. Most of the generation units are connected to the MG through inverters controlled by droop controller. Application of this controller leads to severe drops in voltage and frequency following the events such as load switching, loss of generation, while it guarantees that MG maintains stable. The frequency or voltage drop may lead to tripping of the protection relays; however this condition is not desired from protection point of view at all. The objective of this paper is to propose a novel controller for inverters in islanded MG that can decrease voltage drop in addition to droop controller advantages. Moreover, the proposed controller is able to restore the voltage magnitudes to the rated range during steady state operation. The effectiveness of the proposed controller is demonstrated through comparison of the simulation results with conventional droop controller