Survivability of synchronous generator-based distributed energy resources for transient overload conditions in a microgrid

The synchronous generator-based distributed energy resource (DER) is widely used nowadays due to its low cost and simple controls. However, the requirements for power delivery in a microgrid can be stringent due to the harsh demands. Frequent overloads can occur during the microgrid transition between grid-connection and islanded operation. Therefore, it is very important to have a clear understanding on the survivability of a synchronous generator-based DER for transient overload conditions. Recently, experimental tests on survivability of the DER were carried out in the Consortium of Electric Reliability Technology Solutions (CERTS) Microgrid Testbed at American Electric Power. In this paper, an in-depth analysis of the synchronous generator-based DER operation during transient overload conditions is presented. The key relationships governing the system dynamic behavior are investigated to design the load shedding scheme for survivability of the synchronous generator-based DER. Several case studies are presented to demonstrate the validity of the proposed load shedding methods.