The clique approach to identifying critical elements in gas transmission networks

Abstract

We consider the gas transmission network operating on the territory of the Russian Federation. This network includes gas fields, gas consumers, nodal compressor stations, underground gas storages, which, depending on the given scenario of the system operation, can act as gas sources or gas consumers. The nodes are connected by means of gas pipelines. Because natural gas is used in heat and power engineering and electricity, the gas transmission network may be exposed to terrorist threats, and the actions of intruders may be directed both at gas production facilities and gas pipelines. To simulate intruders attacks, a model of the attacker-defender type was proposed. In this model, the defender, represented by the system operator, solves the problem of finding the maximum flow to meet the needs of gas consumers. The attacker, in turn, attempts to minimize the maximum flow in the gas transmission network by excluding either nodes or gas pipelines. Gas transmission networks in Russia and Europe are very extensive, ramified, and have many bridges and reserve gas pipelines. Therefore, to inflict maximum damage to the system, attacks on cliques, that is, on several interconnected objects, are modelled. The article presents the results of test calculations, in which we identify the most significant combinations of objects in the gas transmission network in terms of the potential threat from terrorist attacks.