Interdependency in smart grid recovery

The pervasive use of information and communication technology (ICT) in the future power grid creates an interdependent system: ICT systems depend on power supply and the power grid depends on information channels and systems for monitoring and controlling. The automation of processes with ICT can reduce the most frequent failures and decrease their consequences. However, the added complexity and the tight integration comes with new failure sources and increased mutual dependencies between the systems and opens the possibility for more catastrophic failures. In this paper we focus on these interdependencies between the power grid and ICT in different phases of the recovery process of a power failure. We model the dependencies and quantify the effect of using smart monitoring devices in the detection phase. The analysis shows that adding battery backup into the communication network is a good measure to delay the interdependency effect encountered. The study of scenarios with different degrees of battery support, number of repair crews and fault detection mechanisms indicates that while automation can reduce the human effort needed for the most frequent failures, it can lead to longer down times in less frequent incidents, if no prevention measures are taken. Finally, we show that the skill sets and training level of the repair crews play a crucial role and can be used to prevent the negative effect in low frequency incidents.