Abstract
We have made several observations. (1) The propagation of failures is confined within a certain range characterized by electrical distances. (2) The electrical distance between consecutive failures may not necessarily increase with the size of the network. (3) We observe that in the intermediate stage of cascading failure propagation, a power system may form a chain-like island. Then, with the propagation of cascading failures, the chain-like islands break into more islands. An improved understanding of this feature enables a more accurate estimation of the stages of cascading failure propagation of the system. (4) The topological variations of a system in cascading failures show a right-skewed distribution, with a few cases of extreme values. (5) The majority of the total system loss in cascading failures can be attributed to several specific failure events. Thus, it is imperative to prevent the occurrence of such failure events to minimize system loss in cascading failures. (6) Statistical analysis shows that voltage instability events play a significant role in cascading failure propagation.
Author Comment
There is still much to explore in the cascading failure process.
