A complex network theory analytical approach to power system cascading failure-From a cyber-physical perspective

The modern electric power grid is evolving rapidly into such a state that distributed controllers and two-way energy and information flow are replacing the traditional paradigm of electricity distribution and energy management. Therefore, a power grid coupled with a communication network is playing a pivotal role in establishing modern electric power systems. Previous cascading failure analysis in power systems focused more on the physical network, while falling short of investigations on the coupling effect of interdependency of the integrated electricity and communication networks, i.e., cyber-physical power systems. To address such a pressing issue, this study introduces a novel stochastic cascading failuremodel, considering the interdependency between the cyber network and power network. Amultiagent system and a novel protection relay model are incorporated into the proposed model. To apply the proposed analytical method, a test power system, the IEEE 68-bs power system, is used to study the impacts of a range of interdependencies and cyber network topological structures on the cascading failure. Simulation results show the necessity and effects of consideration of cyber communication network when investigating power system cascading failures. The study also provides useful information on robustness and vulnerability of a particular power grid, given different communication topologies and interdependencies.