Cyber-contingency evaluation for multiple hypothesized substation outages

The transformation of substation operations from mechanical relays to microprocessor-based intelligent devices has enhanced the communication framework for power system protection. In recent years, the implementation of Internet protocol (IP)-based communication between a substation network and control center has raised its criticality with regard to potential cyber-threats. This paper is concerned with cyber-contingency evaluation based on the computer network environment of a power system. The proposed algorithm demonstrates online impact evaluation capabilities and mitigation approach of substation combinations and computing time, utilizing the real-time measurements from remote terminal units (RTU). The combinations of hypothesized substation outage, the reduction of the scenario combinations and time for simulation, are discussed by enumerating credible impact factors. Simulation results using IEEE-118 and IEEE-30 bus systems have proven the feasibility of the studies within a limited timeframe.