LAUSR

: In case of system contingencies, improving the continuity of the electrical supply by islanding capabilities is of great interest. Besides, reconnecting the power network after an islanding event is also an important issue for maintaining the power system stability. This paper investigates the disconnection and reconnection of a microgrid consisting of two DG voltage source inverters in case of a grid disturbance. The main problem is to achieve a smooth transition between both modes of operation by implementing proper control strategies for the DGs and incorporating a robust synchronization controller. The synchronization controller is implemented to synchronize the microgrid with the main grid after an unintentional islanding condition. Flip flops are utilized to manage the set and reset operation of the static switch and the DG VSI operation mode depending on the network status. The system performance under the short circuit condition has been validated through simulations using SimPowerSystems toolbox in Matlab/Simulink software.