A Phase Angle Synchronization Method for a Microgrid with Diesel Generator and Inverter-Based Sources

Providing the interaction between Distributed Energy Resources (DERs) is one of the main functions of Microgrids (MGs). In order to provide continuity and quality of power supply to local loads, MGs must be able to safely operate on islanded mode and grid connected mode. Therefore, to guarantee the smooth transition between islanded to connected mode without high transients, it turns essential the synchronization of frequency, magnitude, and phase angle values of the MG voltage to the main grid voltage. This paper analyzes a phase angle synchronization method based on droop control applied into a MG with a diesel generator and inverter-based sources. Different scenarios are analyzed showing the effectiveness of the method. The results show that the MG experiences minor transients when the inverter-based source is controlling the MG phase angle during the synchronization process.