Voltage and frequency of microgrids (MGs) are strongly impressionable from the active and reactive load fluctuations. There are several voltage source inverters (VSIs) interfaced distributed generations (DGs) by specific local droop characteristics in a MG. Change in load of a MG may lead to imbalance between generation and consumption and it will change the output voltage and frequency of the VSIs according to the droop characteristics. If the load change is adequately large, the DGs may be unable to stabilize the MG. In the present paper, fuzzy logic is used to optimally tune the coefficients of droop control based frequency and voltage regulation in an AC microgrids.
