Analysis of Cyber Attack and Defense in Process Bus of Digital Substation by Game Theory

The use of smart substations based on digital technology is increasing in the power system. In these substations, according to the data transmission from different levels to intelligent devices of process bus, makes them susceptible to the cyber-attacks. In this paper, cyber attacks are made to the sensors of process bus in three hardware equipment including switches, merging units and intelligent control units. Analysis of the attacks by attackers and created defense through defenders has been assessed with game theory. Regarding to the Nash Equilibrium point for the suggested game, the best attack and defense strategy is determined. According to the proposed method, the damage to the process bus sensors of digital substation can be specified. Optimal defense budget is estimated for cyber security through assessment of cyber defense strategy.