A synchronization technique for microgrid reclosing after islanding operation

The future electric grid concept will cover some small parts to be disconnected and work in an autonomous way isolated from the main utility. Control of microgrids - composed by the couple distributed sources-local loads - with the competence of operating in grid-connected and island mode is a trending research area. The presence of an efficient algorithm for synchronizing the microgrid with the main grid every time the reclosure is allowed is crucial for assuring a safe operation. The synchronization system presented in this work is compounded by two elements: Dual Second Order Generalized Integrator (DSOGI) and stationary reference frames phase-locked loop (SRF-PLL). Besides, the voltage control of the microgrid plays a great role in the synchronization system performance.