A DLL-based Router Scheme for the Process-layer Network in Smart Substations

With the extensive utilization of Intelligence Electronic Devices (IED), the modern smart substation is regard of a typical Internet of Things (IoT) system. The process-layer network in smart substations, which carries the measurements and control signals, needs to operate reliably in the face of unforeseen failures and external malicious attacks. In this paper: i) a mathematical framework for the process-layer network, attacks, and signals is modeled; ii) fundamental network performance limitations from system-theoretic and graph-theoretic perspectives are characterized; and iii) A DLL-based Router Scheme (DRS) is designed to ensure the network performance for the effective operation of IoT. Finally, we validate our design through a series of cases, and the results show that the designed DRS is effective to smooth the network performance.