Abstract
The increasing number of renewable energy sources and their fluctuating nature add significantly to the growing complexity of the power grid. Thus instabilities due to, e.g., line overload, occur more often, increasing the risk of failures. A single failure can originate cascading events and finally end up in a blackout. Reactive control actions aim to overcome such failures a posteriori, whereas proactive ones prevent failures, contributing towards a self-healing and self-organizing smart grid. Moreover, the involvement of communication networks into grid monitoring, management, and control introduces an interdependency between these two systems, which increases the risk of instabilities due to propagation of failures from one system to another. This paper gives an overview of detection and mitigation methods of cascading failures in power grids and communication networks and presents the challenges and open questions in managing such failures in interconnected networks.