Integrated State & topology estimation based on a priori topology information

This paper addresses the simultaneous estimation of state variables and network topology in the context of power system real-time modeling. The proposed method assumes that selected substations are modeled at the bus section level, and circuit breakers and disconnects are explicitly represented. Available information on the statuses of such switching branches are then treated as a priori topology information to be processed by a specialized estimator. The presumed topology will eventually be either validated or corrected by using the information conveyed by real-time measurements. An algorithm based on a fast version of orthogonal Givens rotations is employed to solve the integrated state & topology estimation problem. The proposed method preserves the bad data processing capabilities of weighted least-squares state estimators. The performance of the integrated state & topology estimator is assessed through its application to test systems derived from IEEE benchmark networks.