Optimal Cyber Defense Strategy of High-Voltage DC Systems for Frequency Deviation Mitigation

Abstract

As a critical infrastructure for bulk power transmission in power system, the high-voltage DC (HVDC) transmission system faces the problem of potential cyberthreats. The controllability of the HVDC system heavily relies on the measurements and corresponding communication systems, which makes the HVDC system vulnerable to cyberattacks. This paper proposes an optimal sequence of cyber defense strategy for HVDC transmission system to minimize the frequency deviation caused by cyberattacks on measurements spoofing. The whole sequence of the cyberattack and cyber defense strategies are modeled as a multi-stage attack-defense decision problem, which is transferred into a single-level mixed integer quadratic programming (MIQP) problem with the assumption of the simple if-else cyberattack strategy. The effectiveness of the optimal cyber defense strategy is verified in a two-terminal HVDC transmission system.