The modern electric power grid is one of the most complex networks, and its highly interconnected nature increases vulnerability when transmitting power vast distances from generation to consumption. For instance, during power grid contingencies (e.g., cyber/physical attacks on transmission lines or generators), this interconnection nature accelerates the propagation of failures throughout the system, and causes cascading failure blackouts. Thus, finding the most vulnerable components (e.g., buses or generators) is important for power grid defense. In this paper, a new definition of load has been proposed by taking power flow into consideration. The self organizing map (SOM) based approach is proposed to cluster the nodes (i.e., buses) in IEEE 39-bus benchmark. The most vulnerable node in each cluster is determined based on its load information to form an initial “victim set”. We use percentage of failure (PoF) to compare the performance of proposed SOM-based approach and the traditional load based approach during cascading failure process. In addition, the transient stability of the power system is further studied using both approaches. Our results show that the SOM based approach of victim selection is more efficient than traditional load based strategy.
['Shiva Poudel', 'Zhen Ni', 'Timothy M. Hansen', 'Reinaldo Tonkoski']
Cascading failures and transient stability experiment analysis in power grid security