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The smart grid provides efficient and cost-effective management of the electric energy grid by allowing real-time monitoring, coordinating, and controlling the system using communication networks between physical components. This inherent complexity significantly increases the vulnerabilities and attack surface in the smart grid due to misconfigurations or the lack of security hardening. Therefore, it is important to ensure a secure and resilient operation of the smart grid by proactive identification of potential threats, impact assessment, and cost-efficient mitigation planning. This paper aims to achieve these goals through the development of an efficient security framework for the Energy Management System (EMS), a core smart grid component. In this paper, we present a framework that combines formal analytic with PowerWorld simulator which verifies the solution model to investigate the feasibility of false data injection attacks against contingency analysis in the power grid. We evaluate the impact of such attacks by running experiments using synthetic data on the standard IEEE test cases.
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Impact of Stealthy Attacks on Optimal Power Flow: A Simulink-Driven Formal Analysis
Optimal Power Flow (OPF) is a crucial part of the Energy Management System (EMS) as it determines individual generator outputs that minimize generation cost while satisfying transmission, generation, and system level operating constraints. OPF relies on a core EMS routine, namely state estimation, which computes system states, principally bus voltages/phase angles at the buses. However, state estimation is vulnerable to false data injection attacks in which an adversary can alter certain measurements to corrupt the estimator's solution without being detected. It is also shown that a stealthy attack on state estimation can increase the OPF cost. However, the impact of stealthy attacks on the economic and secure operation of the system cannot be comprehensively analyzed due to the very large size of the attack space. In this paper, we present a hybrid framework that combines formal analytics with Simulink-based system modeling to investigate the feasibility of stealthy attacks and their influence on OPF in a time-efficient manner. The proposed approach is illustrated on synthetic case studies demonstrating the impact of stealthy attacks in different attack scenarios. We also evaluate the impact analysis time by running experiments on standard IEEE test cases and the results show significant scalability of the framework.
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- PAR ID:
- 10056668
- Date Published:
- Journal Name:
- IEEE Transactions on Dependable and Secure Computing
- ISSN:
- 1545-5971
- Page Range / eLocation ID:
- 1 to 1
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1109/TDSC.2018.2806969
