Multi-phase microgrid resiliency assessment framework against extreme weather events

Abstract

The impact of climate change is leading to a phenomenal increase in the frequency and intensity of high-impact, low-probability (HILP) weather events, which cause widespread power outages. Consequently, there is a pressing need to develop resilient power distribution systems against such extreme events. Presently, the methods and metrics to assess grid resilience against HILP events are at an early stage of development and need further work to make them widely implementable in grid resilience investment planning. To address this issue, this study proposes a Monte Carlo-based framework to evaluate the resilience of distribution systems in the presence of distributed energy resources under two distinct phases: (1) during the event as the system succumbs to the extreme forces, and (2) in its aftermath as the restoration proceeds. This allows power system utilities to analyse the effectiveness of various resilience enhancement strategies for different phases of extreme weather events. The framework also establishes a mathematical relationship to determine the post-event restoration time based on the hierarchical sequence of component repairs, which depends on the inter-dependence of component failures and repair crew availability. The framework's effectiveness is demonstrated through case studies on the modified IEEE 69-bus system.