Nowadays, local power supply systems with their generation with aims of modern control technologies are becoming active (smart) grids, i.e. Microgrid. Microgrid facilities change the vector of power system management into the field of decentralization. One of the advantages of Microgrid networks is that in the mode of parallel operation with an external grid when an emergency disturbance occurs, an accelerated separation occurs followed by a transition to islanding operation. When the external grid disturbance is eliminated, it becomes possible to return to parallel operation, resynchronization and connection to the external grid performed. Due to the stochastic nature of Microgrid load changes, synchronization and reconnection to the external grid lead to power fluctuations and shock moments on the generating equipment shaft. This work aims at investigating a method for synchronizing Microgrid with an external isolated power system. A modified synchronization algorithm developed to reduce the likelihood of shock moments and generator shutdowns was investigated and proposed. The possibility of using a recloser as a unifying element when performing synchronization is presented. Transient parameters by the microgrid connection to an external grid are illustrated. The study results prove the efficiency of the proposed algorithm, which improves the reliability and efficiency of functioning when synchronizing parts of the power system.