An approach to improve dynamic response of VSIs in off-grid Microgrids

Recently, voltage source inverters have been applied in a wide range in order to stabilize Microgrids (MGs). These inverters are controlled based on conventional droop method. This method satisfies power sharing between the inverters in steady state. Besides, it enrolls as the frequency controller in inverter-based systems such as MG. In this paper, a modified droop controller is proposed to improve the response speed of VSI during transient time while the power sharing between them is kept satisfied in steady state. This improvement is very useful to stabilize the frequency of independent MG after events leading to power imbalance. The effectiveness of the proposed method is validated after comparison with the conventional droop method through simulations.