Resilience Framework, Methods, and Metrics for the Prioritization of Critical Electrical Grid Customers

Abstract

One of the main objectives of new operating regimes, such as transactional power systems, is to make the power grid more resilient to catastrophes and disturbances, while at the same time making it possible to supply electricity to the largest number of customers. Although this is true, it is well known among power system operators that not all customers are the same. The consequence of this is that any discussion around the impact of transactional power systems on power system resilience should consider the needs of its critical users (such as control centers, fire stations, and hospitals) over other users. In assessing power system resilience, a metric is needed that gives “bonus points” to those systems that, under all circumstances, can continue to provide electricity to their critical users. In order to serve as a parameter in the assessment of power grid resilience, the research presented here discusses the proportion of critical loads existing in critical infrastructures. Once the critical loads are characterized, the next step is the inclusion of these loads in resilience metrics. This paper proposes resiliency metrics in which certain customers (those categorized as critical) are assigned a higher weight than others. One thing to keep in mind is the fact that there is no one-size-fits-all approach for all power systems, and that the assignment of such weights to customers can vary significantly from one operator to another based on their unique systems and the current and expected states of their critical customers.

Reconceptualizing Reliability Indices as Metrics to Quantify Power Distribution System Resilience

“…One study [8] analyzed storm-related historical customer outage data to establish storm-based SAIFI and SAIDI, depicting the power system's performance during such events. Another gave emphasis on the varying resilience needs of critical loads from other grid users [9]. Present regulations [10] on power distribution system performance concerning extreme events, particularly, Major Event Days, center on reliability assessments and metrics focusing on outages attributable to such days.…”