Robust Online Overhead Transmission Line Monitoring with Cost Efficiency in Smart Power Grid

In this work, we investigate a cost-efficient strategy to implement robust online overhead transmission line monitoring for stable energy transfer in smart power grid. As a first step, we first present an analytical framework to evaluate communication performances of wireless sensor networks installed for the real-time monitoring of overhead power transmission line, wherein each tower performs fountain code (FC)-based transmission for guaranteeing transmission reliability between each tower and a substation. Then, we evaluate communication performances given in terms of successful FC-based transmission probability and its end-to-end delay for each tower. Further, our analysis helps formulate an optimization problem that aims at minimizing the total number of activated wide area network (WAN) communication modules deployed on towers(i.e., minimizing the total monetary cost required to use WAN communications), while simultaneously supporting three different types of communication quality of service (QoS) requirements (e.g., reliability, delay, robustness).To find the solution of the problem, we propose the Path Decision in the order of the Farthest Towers (PDFP) algorithm, which enables to find a suboptimal-solution of the problem in real-time. The key idea of PDFT algorithm is that paths (i.e., whether to use a WAN communication module) are sequentially determined in the order of towers farthest from the substation. To identify the validity of the proposed algorithm, we conduct performance evaluations with using public topological and geometrical information of an actual national power grid in Korea. Performance evaluation results show that the proposed PDFT algorithm can find towers that need to activate their WAN communication modules for guaranteeing diverse QoS requirements in real-time, as compared to an optimal-solution algorithm without significant difference in total number of activated WAN communication modules.