Probabilistic transmission expansion planning considering risk of cascading transmission line failures

摘要

Recent studies have shown that power system blackouts occur much more likely than might be expected,rnand their probability distribution follows power law. Cascading outages have been reported as the majorrncause of the large blackouts; therefore, the risk of cascading outages is significant and should be consideredrnin operating and planning assessments of the power systems. The Oak Ridge National Laboratory,PowerrnSystems Engineering Research Center and University ofAlaska (OPA) is a model developed on the basisrnof self-organized criticality to study cascading outages of transmission lines. In this paper, a modified version of the OPA model is used for considering risk of cascading transmission line outages in transmissionrnexpansion planning. The proposed methodfinds a set of effective candidate lines having higher capabilityrnfor suppressing cascading outages; then, the original OPA is exploited over the planning horizon to analyzernlong-term reliability of the system. The benefit of each prospective transmission line is derived by the following two innovations in calculating the risk of blackouts: (i) the power law for finding the probability ofrnblackouts; and (ii) a nonlinear estimation of the cost of the blackouts. Accordingly, the savings associated torneach candidate line is calculated. These values are used tofind the optimal plan using benefit/cost analysis.rnTwo IEEE test systems are investigated to examine the applicability and scalability of the proposed method.rnThe investigations revealed that the proposed method provides more effective scenarios, which entailrnconsiderable saving to society.