Including ampere measurements in generalized state estimators

Conventional state estimators (SEs) cannot take advantage of all available measurements, like currents flowing through circuit breakers and individual external injections. Current measurements are frequent at the lower voltage levels and their loss implies a reduction of the global redundancy and hence a deterioration of the SE filtering capability. In this paper, a methodology is presented allowing all current measurements to be included in the model. A generalized state estimator is used in which substations are compactly represented by means of an implicit model. To illustrate the performance of the proposed formulation, several simulations are presented. Results are validated by checking the accuracy of the estimated states and by showing the improved ability to detect and identify bad data and topology errors.