Vulnerability Analysis of the State Estimation Problem under Cyber Attacks on WAMS

Electric power system is a critical infrastructure and loss of its resilience and/or operability can lead to negative consequences for the national economy. Modern power systems based on sophisticated computer and communication technologies are characterized by elevated vulnerability to different types of unauthorized malicious access, i.e. cyber-attacks. Wide area measurement system which is based on the technology for vector measurements with phasor measurement units refers to the subsystems of electric power systems which are the most vulnerable in terms of the aftermath of cyber attacks. In their earlier researches, the authors of the paper suggested a technique for a two-level distributed state estimation based on singling out the areas in the scheme of electric power systems which are monitored using PMU. The PMU measurements coming at a high frequency make it possible to implement fast linear algorithms of state estimation for such areas. The paper will present potential consequences of cyber attacks on WAMS, their impact on the quality of measurements coming to the state estimation problem and use of distributed state estimation algorithms for their identification. Index Term – WAMS, PMU measurements, state estimation, cyber attacks, test equation method, bad data detection.