A critical lines identification algorithm of complex power system

There are a small number of critical lines in power system that play key roles in the process of causing large-scale cascading failure. In order to implement effective control strategy in overload cascading trips and prevent large-scale blackout, it is very significant to identify critical lines in the power system rapidly, especially when the system is in a cascading failure state. According to the characteristic that blackouts usually associate with the large-scale active power flow transferring, this paper proposes the flow transferring index. Based on the idea of steady-state security region analysis of power system, this paper establishes a critical lines assessment model, presents an algorithm which can be used to identify the critical lines in the process of cascading failure. According to the IEEE 30-bus system, this paper constructs a simulation process of a cascading failure by using the OPA blackout model, and validates the correctness of the proposed identification algorithm through simulation.