Real-Time Monitoring of Points of Common Coupling in Distribution Systems Through State Estimation and Geometric Tests

Abstract

This paper presents an extended state estimation method which allows the identification of unexpected power injections at multiple points of common coupling (PCCs) of power distribution grids. The developed state estimator makes use of a three-phase network modeling where active and reactive power injection levels at PCCs are estimated and checked in real time with the values expected by the system operator. The estimation algorithm applies a sparse tableau formulation in which equality constraints are employed to model power injection assumptions at PCCs. The identification of unexpected power injections is then performed using a methodology based on normalized Lagrange multipliers and geometric tests. Simulations conducted on a modified version of the IEEE 34-node test feeder illustrate the accuracy and applicability of the proposed approach, fostering discussions regarding the future of real-time monitoring on power distribution systems.