An availability analysis on SONET ring networks in power grid communications

As the power grid is becoming smarter, communications has become of significant importance to utility companies. For instance, communications is needed in protective relaying for Special Protection Systems (SPS) which is an automated system that takes corrective action in the case of abnormal or faulty conditions. Communications is also necessary for Supervisory Control and Data Acquisition (SCADA) applications, which is used to collect data and monitor the conditions at electrical substations. Therefore, providing reliable communications is a necessity in order to maintain a reliable and sustainable power grid. This paper presents an availability analysis on ring networks of a Synchronous Optical NETwork (SONET) which is a standard commonly used in communications within utility companies. Optical fiber used in SONET can fault on numerous conditions that are unpredictable, which is a main reliability concern for power grid communications. In this paper, estimation methods are presented and Markov chains models are demonstrated to analyze the availability and explore trade-off issues regarding the SONET ring networks.