Reduced substation models for generalized state estimation

This paper deals with the problem of including detailed substation models in state estimators so that topological errors and/or bad internal data can be detected and identified. Instead of analyzing constraints and state variables related to individual circuit breakers, the whole substation is reconsidered in the light of topological properties, leading to a model where zero-injection constraints are not explicitly handled. In addition, it is shown how, if the new state variables are selected keeping certain rules in mind, the resulting constraints can be easily transformed into equivalent constraints, many of which appear as critical. This allows a reduced model to be used without losing any capability to perform error analysis.