Cyber security assessment in PMU-based state estimation of smart electric transmission networks

The adoption of a massive number of synchronized phasor measurement units (PMUs) supporting the wide-area measurement system (WAMS) in current electric transmission networks brings direct benefit in provision of accurate and timely network measurements, but also exposes a set of outstanding technical challenges in security aspect. This paper looks into the security problem of state estimation in WAMS in the context of cyber-physical system (CPS) which often exhibits complex structural characteristics and dynamic operational phenomenon. Typical attacks on PMUs and adverse impact on network state estimation are explored and studied through carrying out a set of simulation experiments using the IEEE 14-bus transmission network model. The preliminary numerical result quantifies the impact of PMU measurement data tampering on the state estimation accuracy and confirms that the PMU-based state estimation potentially can be significantly affected by various forms of cyber attacks.