Chapter Seven - Microgrids as a resilience resource in the electric distribution grid

Abstract

The electric distribution system (EDS) has traditionally possessed a radial architecture with a strong connection to the bulk power source, the transmission system. However, the rapid deployment of distributed generators (DGs), advanced telemetry, the capability of both manual and remote control, and analytics have enabled the concept of micro-grids (μ-grids) to be realized, where a portion of the EDS has the capability to operate islanded from the main grid enabled by sufficient flexibility in the local generation, energy storage, and demand response. Typical μ-grid formation has well-defined electrical boundaries enabled by switching operation. During low-probability, high-impact (LPHI) events, μ-grids disconnect from the main grid and operate in islanded mode, there by serving critical loads. In this chapter, we discuss the strategies and concepts that enable resiliency through μ-grids. Existing research deals with the formation and control of μ-grids with a tendency to focus on a broader concept of system survival during an LPHI event. However, there is no solid approach developed for engineers and researchers to employ μ-grids’ resourcefulness to serve as a resiliency asset during an LPHI event. This book chapter will enable readers to understand the key features of μ-grid resiliency, evaluation of resiliency and the challenges, and the future of μ-grids as a resiliency resource.