Dynamic Reliability Assessment of Cyber-Physical Energy Systems (CPEs) by GTST-MLD

Cyber-Physical Energy systems (CPEs) are highly connected and remotely controlled systems for energy production, transmission and distribution. Failures of CPEs can occur in both their cyber and physical parts and may, in both cases, result in significant economic losses, service interruption and, even threats to the environment and the population. Traditionally, safety and security of CPEs are addressed separately, the former dealing with failures in the physical part, the latter with breaches in the cyber part. While physical aging is often accounted for, it is not for the cyber elements although it may have an impact on CPEs controllability, stability and, ultimately, reliability. In this paper, we propose a dynamic reliability assessment framework that embeds a multi-state cyber aging model of literature into a Goal Tree Success Tree-Master Logic Diagram (GTST-MLD) that accounts for both stochastic hardware components failures and cyber aging that may open breaches for cyber attacks to the control system. The digital Instrumentation and Control (I C) system of the Advanced Lead-cooled Fast Reactor European Demonstrator (ALFRED) is considered as an example to show the applicability of the GTST-MLD based dynamic reliability assessment method proposed.