Measuring Cascading Failures for Smart Grids Vulnerability Assessment

Cascading failures is a new vulnerability to the emerging of interdependent networks where two networks are depending on one another. In this paper, we propose an analytical model based on centrality and distance measures to calculate the size of cascades. The betweenness centrality is a topological metric that can be used to identify node criticality. The hopcount is a distance related topological metric which can be used to determine the shortest paths from the most critical node to every other nodes. A node failures can lead to an avalanche of cascading failures due to dynamics load redistribution. The size of the avalanche is depending on the criticality of the failed node. When the most critical node failed, the failures can quickly propagate along its shortest paths to every other nodes. We analyze the proposed analytical model and also present the analytical results in comparison to the simulation results so as to validate its effectiveness.