Analysis of action mechanism of graphite bombs and reaction method of power system

The short circuit collapse problem of electric power system attacked by graphite bombs was investigated. The harm of graphite bombs and the vulnerability of electrical network were analyzed. Two kinds of failure modes called direct short circuit failure and indirect short circuit failure were presented accordingly. The arc generation mechanism of conductive filaments dispensed from graphite bombs was analyzed and the concept of compulsively consecutive arc was presented. Then the verifying experiments under the condition of high voltage and small current were done. The short circuit blockade principle of electric power system by graphite bombs was also analyzed. In order to react to the attack of graphite bombs effectively, the clearing methods of conductive filaments such as mechanical removal, combustion and lightning impulse were presented which are helpful to recover the current supply capability of electric power system rapidly.