Mitigation of Cascading Outages Using a Dynamic Interaction Graph-Based Optimal Power Flow Model

TL;DR

This paper introduces a real-time mitigation approach for cascading power outages using a Dynamic Interaction Graph-based optimal power flow model, improving accuracy in identifying vulnerabilities and controlling outage propagation.

Contribution

It develops a novel Dynamic Interaction Graph that adapts to grid changes and integrates it into an optimal power flow model for effective outage mitigation.

Findings

Demonstrates improved identification of vulnerable lines in IEEE 118-bus system.

Shows effective mitigation of outage propagation through the proposed control strategy.

Validates the approach's effectiveness with numerical simulations.

Abstract

Online decision support for effective mitigation actions against propagating cascading outages in a power grid still poses a big challenge to grid operators. This paper proposes an online mitigation strategy against cascading outages using an optimal power flow model based on a Dynamic Interaction Graph. For a given power grid, its interaction graph, also called an interaction model, was proposed in recent literature, which is composed of components and links that have large contributions to outage propagation. Differing from a conventional interaction graph, a Dynamic Interaction Graph can adaptively update its parameters with changes of grid topology and hence is more accurate in online identification of the most vulnerable transmission lines and likely outage propagation paths for mitigation. Further, the paper introduces an optimal power flow model based on the proposed Dynamic Interaction Graph for determining the optimal control strategy to maintain transfer margins of vulnerable transmission lines and effectively mitigate outage propagation. The numerical results on the IEEE 118-bus system demonstrate the effectiveness of the proposed models and associated control strategy.