Numerically-robust techniques for the monitoring of power system operations

Presents a brief survey of the major advances on numerical techniques to solve the power system state estimation (PSSE) problem. A brief review of the conventional batch estimator based on the solution of the normal equation is presented, together with a discussion on its performance from a numerical point of view. Two numerically robust techniques are described for the solution of the PSSE problem: Golub´s method for the solution of the weighted least squares (WLS) problem of a PSSE batch processor, using the Householder orthogonal transformations; and Givens method for the sequential WLS state estimators, using orthogonal transformations performed by rows. A discussion on the sparsity and ordering techniques is included. Finally, a comparison of the two orthogonal techniques with the conventional method, from a computer execution time and storage requirement point of view, is also presented. Several numerical examples are used for such a comparison.