Design for distributed energy resources

A restructured electric distribution network in the electric power system employing a large number of small distributed energy resources (DER) units can play significant role in improving the level of system reliability and providing service differentiations. The present practice allows small-scale integration of DER at distribution levels, with the overall penetration level being kept low for preventing adverse impact on system operation coordination and traditional control equipment actions. The restructure of the electricity network based on microgrid architectures is able to facilitate large-scale DER interconnection into medium/low voltage (MV/LV) distribution systems and offer mechanism to for entirely utilizing benefits of DER. A microgrid also may contain MV/LV distribution systems and clustered loads served by single or multiple DERs. A utility microgrid also can provide ancillary services that may involve local supply of reactive power and premium power quality.