A Signature-Based Analysis for Topology Error Detection in Distribution System State Estimation

In distribution systems, distribution system state estimation (DSSE) is a common approach for real-time monitoring. To ensure system reliability, the distribution system topology is frequently changing and some changes may not be monitored or known by the system operators. Common unmonitored topology errors, like capacitor failure and load transfer, negatively impacts the accuracy of DSSE results. Bad data detection(BDD)-based methods have been used for monitoring of such topology errors, but is limited in its ability to fully detect and identify the presence and location of these common unmonitored topology errors as topology is not a measured component. However, BDD can be improved to enhance its ability for topology error monitoring and its results can be utilized to help further pinpoint the type of topology error and its location. The main contribution of this paper is the adoption of a new approach that utilizes signatures in the BDD results to 1) detect the type of topology error present, 2) localize the topology error to a smaller section of the system. The paper shows this approach enhances the ability to use DSSE and BDD results to accurately monitor for these commonly occurring unmonitored topology errors like capacitor failure and load transfer. Case studies using sample realistic distribution feeders based on real feeder data is provided to illustrate the ability of this new approach.