Expected Failure Method and Its Analysis for Safety Evaluation in a Cyber-Physical Power System

With the development of communication technology, power and information systems have become deeply coupled and have become the most massive and complex cyber-physical power systems (CPPSs), resulting in certain risks to the safe operation of power systems. In this paper, a CPPS security assessment method based on the expected failure method and considering combined information attacks is proposed. Due to the large number of nodes in modern information systems, enumerating all possible combinations of system failures for evaluation and analysis is unrealistic. By considering the topological relationship of the CPPS and the electrical properties of coupled physical nodes, the idea of first screening information nodes is proposed in this paper to filter the information nodes. The impact of combined information attacks on the expected physical fault handling process is analyzed, and a safety evaluation index for the distribution network is provided. In addition, the proposed method is applied to the IEEE-118 system and compared with previous evaluation methods to verify its effectiveness.