Iteratively reweighted least-squares state estimation through Givens Rotations

This paper presents a robust iteratively reweighted least squares (IRLS) method for power system state estimation (PSSE). An orthogonal implementation through Givens Rotations to solve estimators based on nonquadratic criteria is introduced. The nonquadratic criteria are defined based on the robust statistical theory. The weights associated with the measurements include the effects of measurement variances and the location where each measurement is taken. Bad data identification is a byproduct of the proposed method. After bad data identification, no reprocessing is required in order to obtain the correct estimates. The method is validated by using the 14-bus, 30-bus and 118-bus IEEE test systems, in addition to a 340-bus realistic system.