On the complexities of interdependent infrastructures for wide area monitoring systems

Electric power systems (EPS) evolved over years from local independent entities towards large interconnected networks monitored and controlled by sophisticated ICT technologies, and which, eventually will be transformed into Smart Grids where also distributed energy sources, storage, electric vehicles and appliances will be active components of the system. Thus, the scale of complexity involved in present and future power systems architectures is significantly greater than in the past. This paper aims to discuss the interdependency between electric power and communication systems under the system of systems concept. The nature and scale of interdependency between these two critical systems is then further analyzed using an example of disturbance on communications and observing the cascading effects on the power system's monitoring process. Specifically, the impact on the state estimation accuracy is investigated, as a result of a communication node failure, which is responsible for transferring Phasor Measurement Unit (PMU) data to the control center.