Reliability Analyses of Wide-Area Protection System Considering Cyber-Physical System Constraints

Wide-area measurement, protection and control systems link the cyber power system with the physical power system to realize a cyber-physical power system (CPPS). This paper proposes a reliability modeling and assessment method for the wide-area protection system (WAPS). The proposed WAPS model takes into account the decision accuracy of protection algorithms with limited available data at the control center, and combines it with the tripping reliability of protection devices in corresponding substations to form the operation accuracy of WAPS. In particular, the directional comparison algorithm used in decision-making is functionally divided into three modules, namely the initiation module, the fault area positioning module, and the faulted element recognition module. The proposed reliability models are established based on the Permutation and Combination method under the assumption that the data acceptance rate of the control center is d. The sequential Monte-Carlo simulation is used to solve the proposed reliability indices. Finally, the WAPS reliability assessment is presented for the IEEE 14-bus system and the key influencing factors are identified and discussed.