Advanced resilience metrics for electricity networks adjacent to telecommunications networks, based on graph theory

This document presents a set of recommended metrics that can be used to assess the resilience of electricity networks, as well as combined multi-infrastructure networks that include electricity. The intended audience includes network operators, policymakers and other stakeholders in the infrastructure industry. The metrics are derived from network science and graph theory, in combination with power system cascading failure modelling. The metrics presented in this document are predominantly designed towards revealing interdependencies between power and telecommunications networks. The metrics presented in this document are as follows: • Power systems telemetry failures and state estimation (TFSE) metric. This metric considers the reliance of power system state estimation on telecommunications infrastructure, and assesses the impact if this fails. • Correlation between network theory parameters and power system cascading failure outcomes – Network Theory Resilience Metric (NTRM). This metric is based on the principle that the fundamental structure of the electricity network significantly affects the development and scale of cascading outages / blackouts. • Cascade-oriented outcome prediction (COOP) metric in modified networks. This metric is expanding the NTRM concept by attempting to predict cascading failure outcomes in networks that have been modified from the original arrangement, by e.g. adding or removing buses and/or branches. This can be used in scenario modelling and reconfiguration planning. • Adjacency (ADJ) metric with other infrastructure networks. This metric expands the NTRM concept further, by considering the fundamental structure of any infrastructure network that is adjacent to an electricity network, and how an outage might cascade across the whole interdependent multi-layer network. The above metrics will be applicable in several functions of the infrastructure industry, but mostly in network operation and planning, as well as restoration team allocation. Since the metrics can reveal which components of the network are most likely to contribute to a widespread outage, these components can be prioritised when compiling operational and disaster response plans. Network expansions can also be designed to minimise widespread outage risks.