Document Type


Date of Award

Spring 5-31-1990

Degree Name

Master of Science in Electrical Engineering - (M.S.)


Electrical and Computer Engineering

First Advisor

Walid Hubbi

Second Advisor

Edwin Cohen

Third Advisor

Bernard Friedland


The effects of weighting matrices that may be used in the Weighted Least Squares (WLS) method when applied to the problem of Power System State Estimation (PSSE) are studied. These weighting matrices include the one usually used in the literature and the one used in the utility PSSE programs

The performances of these weighting matrices are compared using the Monte Carlo simulation technique.

To test the performances of the weighting matrices, a PSSE program is developed, different performance indices for state comparison are defined, and many cases are studied.

Results show that the weighting matrix usually used in literature, 1/σ², and a proposed weighting matrix, 1/σ, give comparable results and are the best of those tested. The weighting matrix used in the utility industry programs offers little or no improvement.