During peak hours of load demand in micro-grid (MG), the power frequency faces more excursion from a nominal value thereby deteriorating the power quality. The main idea is to utilize the EV power during peak load in to a MG system to limit the under frequency deviation and to charge the EV during off peak hours when the generation is surplus. This paper simulates a MG model in MATLAB/Simulink with EV as one of the sources using PID and fractional order PID (FOPID) controller to regulate the frequency deviation. The parameters of PID and FOPID controller are being optimized using genetic algorithm (GA) for improvement in the time response of frequency deviation of MG. The total energy model (TEM) of EV has been used for MG simulation. The optimized parameters obtained for PID, GAPID, FOPID and GAFOPID has been recorded for analysis. The GAFOPID based controller gives the better response for the defined objective function.