A novel power grid reduction technique for a transmission expansion planning problem using a weighted signed graph model

Abstract

In Power System, the aim of Transmission Expansion Planning (TEP) studies is to determine which, where, and when new transmission lines should be constructed at the minimum total cost. The large-scale network (around 10 000 nodes) involved in this problem makes it hard to solve. This raises the need for methods able to reduce the size of the network model while providing a similar solution to the one that would be obtained considering the full size transmission network. We apply the network reduction in two steps: first we find an adequate partition of the original network in a TEP context, then we build the quotient graph associated to this partition. The network partition in our work is computed considering a weighted signed graph. As far as we know, this is the first time this kind of graph is used to apply power grid partitioning. Moreover, the similarity measure between buses is computed based on an estimate of the reinforced grid rather than the existing network. This measure “based on effects” is also new in power grid reduction works.