Argonne National Laboratory

Interconnection, Integration, and Interactive Impact Analysis of Microgrids and Distribution Systems

TitleInterconnection, Integration, and Interactive Impact Analysis of Microgrids and Distribution Systems
Publication TypeReport
Year of Publication2017
AuthorsKang, N, Singh, R, Lu, X
Date Published01/2017
Report NumberANL/ESD-17/4

Distribution management systems (DMSs) are increasingly used by distribution system operators (DSOs) to manage the distribution grid and to monitor the status of both power imported from the transmission grid and power generated locally by a distributed energy resource (DER), to ensure that power flows and voltages along the feeders are maintained within designed limits and that appropriate measures are taken to guarantee service continuity and energy security. When microgrids are deployed and interconnected to the distribution grids, they will have an impact on the operation of the distribution grid. The challenge is to design this interconnection in such a way that it enhances the reliability and security of the distribution grid and the loads embedded in the microgrid, while providing economic benefits to all stakeholders, including the microgrid owner and operator and the distribution system operator.

The interconnection and integration of microgrids into distribution systems can be facilitated, and the presence of microgrids better benefit all stakeholders, if appropriate tools are developed to represent and control microgrids from within the DMS. Such microgrid models and control tools will allow a detailed analysis of the impacts of microgrids on the feeders to which they are connected and the distribution system in its entirety. The tools will also enable interaction with the microgrid that benefits all stakeholders. The models will represent, among other features, the aggregation of DERs and loads within the microgrid and the control functions implemented by the microgrid controller.

This report deals with some of the technical issues related to integrating microgrids into a distribution system and its DMS. It first describes elements of the operation of microgrids within distribution systems, including possible modes of operation and interactions in normal and faulted operating conditions (Section I). It provides background information, in the form of use cases, on some of the internal modes of operation of microgrids that may impact the distribution system, including normal and faulted operation (Section II). It then addresses operating modes in which the microgrid interacts with the distribution system, including power exchanges under normal operation and fault conditions as well as protection coordination (Section III). Finally, it discusses power system analysis tools, such as power flow and fault analysis tools that can be used to analyze the impact of the integration of microgrids in distribution systems (Section IV).