Bilevel Model for Analyzing Coordinated Cyber-Physical Attacks on Power Systems

TLDR

Coordinated cyber‑physical attacks can create undetectable line outages and trigger cascading failures in power systems. The study proposes a bilevel model to identify the most damaging, undetectable physical attacks within an attacker’s budget and discusses countermeasure strategies. The bilevel model is reformulated as a mixed‑integer linear program and solved via a rigorous two‑stage algorithm, validated on IEEE 14‑ and 118‑bus test systems. Case‑study results demonstrate the model’s ability to pinpoint critical attacks and assess the effectiveness of proposed countermeasures on the test systems.

Abstract

This paper analyzes a coordinated cyber-physical attack on power systems, which could lead to undetectable line outages. Coordinated with physical attacks that cause line outages, the two-step cyberattacks comprising topology preserving and load redistribution attacks could mask and potentially exasperate outages to trigger cascading failures. These coordinated cyber-physical attacks are analyzed in a proposed bilevel model, which aims at identifying the most damaging and undetectable physical attacks constrained by attackers' total budget. After being transformed into a mixed-integer linear programming problem, the proposed bilevel model is solved by a rigorous two-stage solution approach. This paper also discusses the relevant countermeasure strategies. The proposed model, the solution algorithm, and the effectiveness of countermeasures are examined by case studies based on the IEEE 14- and 118-bus test systems.