Evaluating multiple reliability indices of regional networks in wide area measurement system

The paper presents a hierarchical structure of Wide Area Measurement System (WAMS) that can satisfy requirements of reliable real-time data transfer. The methods of calculating multiple reliability indices of WAMS regional networks in the protection and recovery survival mechanisms are developed and an equivalent two-state model of a WAMS regional network is presented. The numerical results of an example indicate that the meshed WAMS regional network can provide a very high reliability level. The reliability of the regional network can be enhanced by selecting an appropriate location of Phasor Data Center (PDC) or by improving availability of crucial optic fiber links in the protection mechanism. In the dynamic recovery mechanism, however, these measures may not be effective and thus the key consideration should be put on how to timely restore data transfers after a communication contingency.