Transient stability analysis of power systems via aggregation on subsets

Abstract

The decomposition-aggregation method is used to carry out the transient stability analysis of an N-machine power system (the transfer conductances are included). The system is decomposed using either pair-wise or triple-wise decompositions. Elements of the system aggregation matrix are obtained by applying a new majorization procedure. In this procedure, the whole space is divided into a number of subspaces, each of them involving a number of system state variables. For every subspace, the majorization is carried out considering only positive interactions. In this way, the proposed majorization procedure can decrease the number of interactions to be majorized simultaneously, and produce a system aggregation matrix with weaker off-diagonal elements. Two power systems, with three and seven machines, are used as numerical examples. An estimate of the asymptotic stability domain of the seven-machine system is determined. It is found that the developed majorization procedure can lead to a considerable reductio...