Decentralized cyber-physical security applications for the future grid energy management system

Abstract

The objective of this work is to enhance the state estimator application in the energy management system. The state estimator is responsible for processing raw power system measurements received from substation equipment in the field and filtering out the errors to determine the most likely state of the power system in terms of bus voltage magnitudes and angles. Because the state estimator solution serves as the input to other critical downstream applications in the energy management system, such as contingency analysis and optimal power flow, it is key that a unique solution can be found quickly, and that the solution is accurate. The changing nature of the power grid is introducing new challenges for the state estimator. The first challenge is the need to process more data in less time. To address this issue, we introduce decomposition-based state estimation. The second challenge is the need for more robust power system cybersecurity. We present a cyber-physical security assessment co-simulator that uses an enhanced state estimator to identify whether a control command is malicious. We also introduce a novel approach for N-1 RTU cyber-physical security assessment that ranks RTUs by how critical the impact of their loss is on the state estimator.