The main goal of this paper is to develop a control for maintaining the state of charge of the energy storage system which is used to regulate the power/frequency of microgrids and will also act as a spinning reserve to micro-grid fluctuations. SYSTEM DESIGN: One microgrid consists of a DEG, solar PV and wind power, and load. The other microgrid has DEG, wind power, and load. The tie-line connected MMG system has a common ESS. OPERATION CONSIDERATIONS: • In this system, batteries voltage, current, and temperature are controlled centrally. • Tie-line is used to exchange energy between control areas to provide inter-area support in case of a faulted condition. • Algorithm logic here is When the change in frequency (Δf) becomes negative, the ESS supplies power to the system. (This SOC should be more than the predefined value only then ESS will supply power else it won't supply power and once frequency change becomes positive, the system will charge ESS). RESULTS OF RESEARCH: • From 0 to 58s both the microgrids operate independently. • Each DEG supplies the deficit power in the respective MG. • From 58 to 245s surplus renewable energy is available at MG1 and extra energy is transferred from MG1 to MG2 depending on the load demand or stored at ESS. • To operate economically, DEG2 is stopped, and ESS is used as the spinning reserve.