This paper presents a new approach to power system state estimation ba
sed on the application of fuzzy logic. Significant improvements in sta
te estimates are achieved (relative to the weighted least squares algo
rithm) by using a hybrid estimator incorporating fuzzy-logic concepts.
The design of the fuzzy estimator is described. The approach is illus
trated for two sample systems: a 6-bus network and the 30-bus IEEE tes
t system. Numerical and graphical results are presented to illustrate
the superiority of the new method. (C) 1996 Elsevier Science S.A.