Enforcing the N-1 criterion in power transmission networks : an analysis of a theoretical model

Abstract

We construct a numerical model of a power transmission network and analyse the effect of implementing N-1 security constraints. We find that implementing N-1 can have widespread effect on prices and quantities through changes in congestion patterns, particularly by increasing the role low-capacity lines have in causing congestion. This can have considerable implications for optimal investment strategies. Enforcing the N-1 criterion improves the security, but at increased cost of dispatch. While the overall costs increase, it can make individual actors on the market better off, especially the collector of grid fees. Finally we compare N-1 security constraints and other types of security constraints, namely cut constraints and de-rating of lines.