Robust Sequential Steady-State Analysis of Cascading Outages

TL;DR

This paper presents a robust, circuit-theoretic framework for simulating large-scale cascading outages in power grids, incorporating frequency effects and load shedding to improve accuracy and convergence.

Contribution

It extends existing steady-state analysis methods by modeling frequency dependencies and load shedding, enabling more reliable simulation of cascading failures.

Findings

Successfully simulated cascading outages on an 8000-node system.

The framework can identify infeasible operating regions.

Enhanced convergence and robustness over traditional methods.

Abstract

Simulating potential cascading failures can be useful for avoiding or mitigating such events. Currently, existing steady-state analysis tools are ill-suited for simulating cascading outages as they do not model frequency dependencies, they require good initial conditions to converge, and they are unable to distinguish between a collapsed grid state from a hard-to-solve test case. In this paper, we extend a circuit-theoretic approach for simulating the steady-state of a power grid to incorporate frequency deviations and implicit models for underfrequency and undervoltage load shedding. Using these models, we introduce a framework capable of robustly solving cascading outages of large-scale systems that can also locate infeasible regions. We demonstrate the efficacy of our approach by simulating entire cascading outages on more than 8000 nodes sample testcase.