On-line transient stability assessment of an electric power system using a parallel processing state estimator

In this paper a combined on-line hybrid transient stability formulation with a parallel processing state estimator is presented. The transient stability assessment uses a time domain integration scheme to compute the initial system trajectory and the equal area criteria to obtain the transient stability margins and the critical clearing times. The state estimator that provides the pre-fault operating conditions uses a parallel processing approach. In this technique the power system is split into K areas, and each subsystem is supervised by a local control centre. The measurements in each area are collected in the individual local control centre that has at least one computer system for data acquisition, data processing and computation. The computer programs developed by the authors were applied to a multimachine power network. The results obtained with the proposed formulation were compared with the solutions produced by other methods. Finally, some conclusions that provide a valuable contribution to the understanding of the multimachine power system preventive control are pointed out.