Presenting an Index for Evaluation of Power Network Security Using Fuzzy Set Theory

The purpose of this paper is to present an index for evaluation of power network security after terrorist attacks against the network facilities using fuzzy set theory. In order to achieve this goal, a method based on probability and possibility theory is used. In the first step, by using Bayesian network which is a method based on probability theory, the probability of the attack as well as the risk value caused by terrorist activities against the power network facilities was calculated and the network facilities were ranked according to the level of the risk. In the second step, by employing fuzzy load flow and finding the fuzzy parameters related to network performance, the impact of the loss of each component ranked in the first step on power network was investigated. Finally, having calculated the risk value caused by terrorist attacks against the network facilities, an index was provided for evaluating power network security. Also, in order to validate the effectiveness of the proposed method, security index for a specific network was calculated.