IDENTIFYING THE UNKNOWN CIRCUIT-BREAKER STATUSES IN POWER NETWORKS

This paper describes an approach by which the circuit breaker status e rrors can be detected and identified-in the presence of analog measure ment errors. This is accomplished by using the least absolute value (L AV) state estimation method and applying the previously suggested two stage estimation approach in [15]. The ability of the LAV estimators t o reject inconsistent measurements, is exploited in order to different iate between circuit breaker status and analog measurement errors. The first stage of estimation uses a bus level network model as in conven tional LAV estimators. Results of Stage 1 are used to draw a set of su spect buses whose substation configurations may be erroneous. In the s econd stage, the identified buses are modeled in detail using the bus sections and the circuit breaker models while keeping the bus level ne twork models for the rest of the system. The LAV estimation is repeate d for the expanded system model and any remaining significant normaliz ed residuals are flagged as bad analog measurements, while the correct topology is determined based on the estimated flows through the model ed circuit breakers in the substations. The proposed approach is imple mented and tested. Simulation results for cases involving circuit brea ker status and/or analog measurement errors are provided.