Gross error extraction using modified relaxation in power system state estimation

This paper proposes a modified relaxation-based method for gross error iden tification. Toward this end, a participation matrix is defined that consist s of the elements of the residue sensitivity matrix and the corresponding m easurements. It is shown that the sum of row elements of the participation matrix constitutes the residues. The column elements of the participation m atrix is also considered as a source of information of masking, and their s um is quantified as distortion. A set theoretic formulation using large dis tortions and large residues is proposed to indicate the quality of measurem ents. The measurement corresponding to the poorest quality is then correcte d using the modified form of relaxation. The above procedure is repeated se quentially until all residues are within a particular tolerance. The method gives a measurement set very near to the true measurement set.